noun
crimson sea bream
A species of sea bream (Evynnis japonica), often encountered in fishing and culinary contexts.
チダイは関東ではあまり見かけない魚だ。
Crimson sea bream is a fish you don't see much in the Kanto region.
釣り上げたチダイを刺身にして食べた。
We made sashimi from the crimson sea bream we caught.
真鯛 (red sea bream) is a different, more common species; チダイ is a related but distinct fish.
The name likely derives from 血 (chi, 'blood') + 鯛 (tai, 'sea bream'), referring to the reddish color of the fish.