Invertebrates Word Search

Animals without backbones, sorted the way a science unit sorts them, with the answer key on a second page.

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0 of 16 words found

SCORPIONNCSRSWS

WFTTFNROHLUJLNI

CHNHVVISNAILPDN

ROXICERIBMPAEST

ACLNWRDAFMTRHEN

BTOSRTILBKSTEAY

WOBEPEXCSRAHARY

UPSCGBCFCMSRNTO

BUTTERFLYHEONHL

USESTARFISHPEWX

AGRHOTDNIDTOLOQ

TLMLTEISNAJDIRE

LBIMNMPYZFOXDMI

DJELLYFISHJIEFG

BEETLEMOLLUSKDR

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MolluskMOLLUSK
OctopusOCTOPUS
SnailSNAIL
ClamCLAM
AnnelidANNELID
EarthwormEARTHWORM
JellyfishJELLYFISH
InsectINSECT
BeetleBEETLE
ButterflyBUTTERFLY
CrabCRAB
LobsterLOBSTER
ArthropodARTHROPOD
ScorpionSCORPION
StarfishSTARFISH
InvertebrateINVERTEBRATE

16 of 22 words from the Invertebrate Favorites list.

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Answer key: Invertebrates Word Search

SCORPIONNCSRSWS

WFTTFNROHLUJLNI

CHNHVVISNAILPDN

ROXICERIBMPAEST

ACLNWRDAFMTRHEN

BTOSRTILBKSTEAY

WOBEPEXCSRAHARY

UPSCGBCFCMSRNTO

BUTTERFLYHEONHL

USESTARFISHPEWX

AGRHOTDNIDTOLOQ

TLMLTEISNAJDIRE

LBIMNMPYZFOXDMI

DJELLYFISHJIEFG

BEETLEMOLLUSKDR

MOLLUSK, OCTOPUS, SNAIL, CLAM, ANNELID, EARTHWORM, JELLYFISH, INSECT, BEETLE, BUTTERFLY, CRAB, LOBSTER, ARTHROPOD, SCORPION, STARFISH, INVERTEBRATE

Next step Find more insects in the bug word search See where arthropods sit among living things

All 95 words

Mollusks 20

Abalone A sea snail with a flattened, ear-like shell, pearly inside, and a row of holes for breathing.
Chiton A sea animal of the class Polyplacophora, sometimes called a sea cradle or a coat-of-mail shell.
Clam A bivalve with two shells of equal size; many kinds live half buried in the sand.
Conch A medium-sized to large sea snail whose shell typically has a high spire.
Cowrie A sea snail whose shell was the most widely used shell money in the world.
Cuttlebone The hard, brittle internal structure of a cuttlefish.
Limpet An aquatic snail with a cone-shaped shell and a strong, muscular foot.
Mantle The body wall that covers a mollusk's inner organs; in many species it makes the shell.
Mollusk A member of the phylum that holds snails, clams and octopuses; 86,600 living species are recognized.
Nautilus A cephalopod whose name comes from the Greek word for a sailor.
Nudibranch A soft-bodied marine gastropod, often strikingly colored, that sheds its shell after its larval stage.
Octopus A soft-bodied animal with eight limbs, in the same class as squids, cuttlefish and nautiloids.
Oyster A salt-water bivalve of marine or brackish water, often somewhat irregular in shape.

Show all 95 words (82 more)

Mollusks, continued

Periwinkle A small sea snail of the shore between the tides, with a dark, sometimes banded shell.
Radula A ribbon of tiny teeth, often compared to a tongue, that most mollusks use to scrape or cut food.
Shell The hard, chalky case that many mollusks build around their soft bodies for support and protection.
Slug A land gastropod that appears to have no shell.
Snail A gastropod with a coiled shell large enough to pull its whole body into.
Squid A cephalopod with eight arms, two tentacles, big eyes and a long, soft body.
Whelk A meat-eating sea snail with a swirling, tapered shell; many kinds are eaten by people.

Worms 9

Annelid A segmented worm; the name of its phylum comes from the Latin for little ring.
Bristle Worm A mostly marine annelid, also called a polychaete, with a pair of fleshy flaps on every segment of its body.
Earthworm A soil-dwelling land animal of the phylum Annelida.
Fluke A parasitic flatworm whose life cycle needs at least two hosts; the first is usually a snail.
Leech A segmented parasitic or predatory animal with a soft, muscular body that can lengthen and contract.
Roundworm A nematode; most kinds live free and feed on microorganisms, but many are parasites.
Tapeworm A parasitic flatworm, ribbon-like as an adult, whose body is made of many similar units.
Tube Worm The giant kind, Riftia, lives near geologically active parts of the deep sea.
Velvet Worm A long, soft-bodied animal with many legs, in a phylum of its own named Onychophora.

Sponges, Jellies and Corals 12

Brain Coral A rounded colony of polyps whose grooved surface looks like the organ it is named after.
Cnidocyte A cnidarian's stinging cell: it fires a toxin-filled capsule to subdue prey and to defend against predators.
Comb Jelly A sea animal of the phylum Ctenophora that swims by means of groups of tiny hairs called cilia.
Hydra A small freshwater cnidarian, named after a many-headed beast of Greek myth.
Jellyfish A mainly free-swimming sea animal of the phylum Cnidaria, in the medusa phase of its life.
Lion's Mane One of the largest known jellyfish, found in cold waters of the Arctic and the northern oceans.
Man o' War A sea animal of the Atlantic, Indian and Pacific oceans, also known as the bluebottle.
Medusa The body form of a cnidarian that a jellyfish has; the other form is the polyp.
Polyp One of the two body forms of a cnidarian, roughly cylinder-shaped; the other is the medusa.
Sea Anemone A predatory animal of the phylum Cnidaria, named after a colorful flowering plant of the land.
Sponge A filter-feeding sea animal fixed to the seabed; its phylum, Porifera, means pore bearer.
Tentacle A flexible, movable, long organ found in some animals, most of them without a backbone.

Insects 13

Ant A social insect related to wasps and bees; more than 13,800 species have been described.
Beetle Its front wings are hardened into wing cases; with about 400,000 described species, its order is the largest.
Butterfly A winged insect with large, often brightly colored wings that often fold together at rest.
Dragonfly An insect of the order Odonata that flies; some 3,000 species are alive today, most of them in the tropics.
Glowworm An insect larva, or a larva-like adult female, that glows with a light of its own.
Horsefly A large true fly, agile in the air, that prefers sunlight and avoids dark and shady places.
Housefly A gray to black insect with four dark lines on its thorax that has spread around the world with people.
Insect An arthropod whose body has three parts; it has six jointed legs, compound eyes and two antennae.
Mayfly An aquatic insect of an ancient group that also holds the dragonflies and damselflies.
Mosquito A small fly with a slender body; its name is Spanish and Portuguese for little fly.
Moth A winged insect of the order Lepidoptera, the order it shares with the butterflies.
Wasp A narrow-waisted insect of the order Hymenoptera which is not a bee and not an ant.
Water Strider A true bug of the family Gerridae, also called a pond skater.

Crustaceans 11

Barnacle A sea arthropod, kin to crabs and lobsters; many of its species live in shallow water and between the tides.
Carapace The upper section of the exoskeleton or shell of animals such as crustaceans, arachnids and turtles.
Copepod A small crustacean whose name means oar-feet; it lives in almost all fresh and salt waters.
Crab A crustacean with a heavily armored shell that is able to run sideways.
Crayfish A freshwater relative of the lobster, also called a crawfish or crawdad, that breathes through feather-like gills.
Crustacean A mainly aquatic arthropod; the name of its group comes from the Latin for those with shells.
Krill A small crustacean found in all the oceans of the world; its name is Norwegian for small fry of fish.
Lobster A crustacean with a long body and a muscular tail; three of its five pairs of legs have claws.
Prawn A common name for a small water crustacean with ten legs, often a larger shrimp.
Shrimp A crustacean with a long body that gets about mainly by swimming.
Woodlouse A land isopod often found in old wood; in spite of its name it is neither a parasite nor an insect.

Spiders, Scorpions and Many Legs 11

Arthropod An animal with an exoskeleton, a body in segments and paired jointed limbs.
Harvestman An arachnid also known as a daddy longlegs; over 6,650 species have been discovered.
Horseshoe Crab In spite of its name it is no crustacean; it is more closely related to spiders, ticks and scorpions.
Millipede An arthropod with four jointed legs on most segments of its body; its name is Latin for thousand and foot.
Mite A small arachnid, which means it is an eight-legged arthropod.
Molting Shedding the old outer covering during growth, so that a new and larger one can form.
Scorpion A predatory arachnid: eight legs, two grasping pincers and a narrow tail tipped with a stinger.
Silk A protein fiber that spiders spin to make webs, to wrap prey and to protect their young.
Spider An air-breathing arachnid with eight limbs, fangs that can generally inject venom, and organs that make silk.
Tick A parasitic arachnid that lives by feeding on the blood of other animals.
Trilobite An extinct sea arthropod whose name means three-lobed; its group lived in the oceans for almost 270 million years.

Echinoderms 9

Brittle Star An echinoderm that crawls across the sea floor on flexible, serpent-like arms.
Echinoderm A member of the phylum that holds starfish, sea urchins, sand dollars and sea cucumbers.
Feather Star A crinoid that has no stalk as an adult; its kind makes up the largest order of crinoids.
Sand Dollar A flat, burrowing relative of the spiny urchins, known in New Zealand as a sea cookie.
Sea Cucumber An echinoderm found on ocean floors worldwide; the most species live in the Asia-Pacific region.
Sea Lily A crinoid that stays attached to the ocean floor by a stalk as an adult.
Sea Urchin A round, spiny echinoderm; about 950 species live on the ocean bottom, from the shoreline to great depths.
Starfish An echinoderm with arms like the points of a star, also known as a sea star.
Tube Feet Small tubular projections on the underside of an echinoderm, as on the arms of a starfish.

Invertebrate Life 10

Colony Two or more animals of one species that live in close association with, or joined to, one another.
Filter Feeder A water animal that eats food particles or tiny organisms, which it strains out of the water.
Invertebrate An animal that never develops or keeps a backbone; one estimate puts 97% of animal species in this group.
Lancelet A somewhat fish-like animal that has no backbone but is a closer relative of the vertebrates than most such animals are.
Larva A distinct young form that many animals pass through before they change into the next stage of life.
Parasite A living thing that lives on or inside another, its host, and causes it some harm.
Sea Squirt A sac-like marine animal that strains its food from the water and has a tough outer coat called a tunic.
Symmetry A matching arrangement of body parts, as on either side of a line down the center of a face.
Venom A toxin that an animal delivers to another animal through a bite or a sting.
Water Bear A tardigrade: a tiny eight-legged, segmented animal also known as a moss piglet.

How this list was compiled: 95 invertebrate words in eight lists that follow the main groups: mollusks, worms, sponges and jellies, insects, crustaceans, spiders and their kin, echinoderms, and invertebrate life. Facts in the clues were checked on October 9, 2026 against each word's English Wikipedia article (https://en.wikipedia.org/, CC BY-SA 4.0); spellings and plain meanings against English Wiktionary. Licence: own work

How it works

This invertebrates word search opens on 16 words: the group names Mollusk, Arthropod and Annelid, with animals such as Octopus, Snail, Earthworm, Jellyfish and Starfish. The 95 words on the page fill eight lists that follow the main groups.

Read the full guide

Lists that follow the phyla

Mollusks has 20 words, from Snail and Squid to Nautilus and Nudibranch. Worms has 9: Earthworm and Leech are annelids, Tapeworm and Fluke are flatworms, and Roundworm is a nematode. Sponges, Jellies and Corals has 12, and Echinoderms has 9, with Sea Urchin, Sand Dollar and Brittle Star.

Three lists of arthropods

Insects has 13 words, from Ant and Beetle to Mayfly. Crustaceans has 11, such as Crab, Krill and Barnacle. Spiders, Scorpions and Many Legs has 11, with Tick, Millipede and Horseshoe Crab, which is no crab. Invertebrate Life adds 10 words such as Larva, Colony and Venom.

Easy Invertebrates keeps to short names, 22 of them, such as Ant, Crab, Slug and Snail.
Tick Show clues, not words in More options and Earthworm becomes "A soil-dwelling land animal of the phylum Annelida."

Questions and answers

What is an invertebrate?

An animal that never develops or keeps a backbone. Most animals are invertebrates: one estimate puts the figure at 97% of animal species. They range from tiny myxozoans to the colossal squid, 9 to 10 meters (30 to 33 feet) long.

What are the main groups of invertebrates?

The lists follow them: sponges; cnidarians such as jellyfish and corals; flatworms, roundworms and annelids; mollusks; arthropods, which take in insects, crustaceans and arachnids; and echinoderms such as starfish.

Is a spider an insect?

No. A spider is an arachnid with eight limbs. An insect has a three-part body, three pairs of jointed legs and a pair of antennae. Both are arthropods, so the puzzle keeps them in separate lists.

Does the invertebrates word search have an answer key?

Yes. It prints after the puzzle, on a page of its own, with each hidden word ringed. Both pages fit Letter and A4.

All 95 words

Mollusks 20

Mollusks, continued

Worms 9

Sponges, Jellies and Corals 12

Insects 13

Crustaceans 11

Spiders, Scorpions and Many Legs 11

Echinoderms 9

Invertebrate Life 10

How it works

Lists that follow the phyla

Three lists of arthropods

Questions and answers

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