common pill bug; Armadillidium vulgare
A terrestrial isopod that rolls into a ball when threatened; commonly found in gardens and under stones.
When I turned over a stone, a pill bug rolled up into a ball.
Pill bugs prefer damp places.
ダンゴムシ is a broader term for pill bugs in general, while オカダンゴムシ specifically refers to the common species Armadillidium vulgare.
Katakana spelling is common for this organism name; usually written in kana.
Kanji spelling is rare; the word is usually written in kana.
Compound of 陸 (おか, 'land') and 団子虫 (だんごむし, 'pill bug'), referring to the terrestrial pill bug species.