noun
giant Pacific octopus; North Pacific giant octopus
Refers specifically to Enteroctopus dofleini, the largest octopus species. Often contrasted with the smaller 水蛸 (みずだこ).
See also: 水蛸 (みずだこ)
水族館で大だこを見た。
I saw a giant Pacific octopus at the aquarium.
大だこは北太平洋に生息している。
The giant Pacific octopus lives in the North Pacific.
Refers to a smaller octopus species (often the common octopus or a related species), while 大だこ is the much larger giant Pacific octopus.
Compound of 大 (おお, 'big') and 蛸 (たこ, 'octopus'), with rendaku voicing on the second element. The spelling 大だこ is a common mixed kanji-kana representation.