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pill bug

pill bug

6.0
A small land animal that rolls into a ball when touched
  • noun
  • /pɪl bʌg/
  • US
translation icon : bicho bola
  • Aquatic isopods resemble roly-polies (pill bugs) somewhat because roly-polies are terrestrial isopods.

Examples

  • Our pill bugs' only hope of survival, is our mistress of the high wire, Rosie!

  • She looks like a pill bug.

    Fiction book (1998)
  • If you watch closely, you can see the mass escape: ants, pinchers, and pill bugs flee the burning forest, every man for himself.

    Fiction book (1992)
  • Aimed directly at the flypaper, are Tuck and Roll, the pill bug cannonballs!

  • In fact, they can look damn-near cute—almost like little roly-poly pill bugs.

    Blog text (32)
  • To the untrained eye, larval cephalopods resemble alien heads, krill look like diminutive shrimp, and amphipods look like tiny pill bugs.

    Academic text (2011)
  • He found a pill bug under a rock in the garden.

  • The children were excited to see a pill bug roll into a ball when they touched it.

  • After a rain, you can often spot pill bugs crawling on the ground, seeking shelter.

Synonyms

bug
vspill bug
623 1.0

A small insect like an ant or beetle

is a specific small crustacean that curls into a ball rather than an insect
insect
vspill bug
341 1.0

A small animal with a body in three parts, six legs and often wings

is a land isopod with a segmented body that curls into a ball
Armadillidiidae
vspill bug
  • Specialized
9.9

Small land animals like pill bugs that roll into a ball when threatened

is the common name for these animals noted for rolling into a ball
Oniscidae
vspill bug
  • Specialized
9.9

Small grey land animals with many legs that live under logs and eat dead plants

is the form that specifically rolls into a ball when disturbed

Surface Forms

pill bug singular
pill bugs plural

Morphology

pill + bug

The compound is compositionally transparent: 'pill' conveys a pill-like shape/appearance and 'bug' denotes a small creature, so a B1 learner who knows both words can infer it refers to a small, pill-shaped critter. They might not know precise taxonomy or the rolling behaviour, but the basic referent is predictable from the constituents and common noun–noun compounding patterns.

Etymology

Pill bug gets its name from the animal's habit of curling up into a tight round shape that looks like a small pill. People call it a bug because it is a small crawling creature, so the name reminds us that this little animal rolls into a ball for protection.