also: りょうけい
noun
good-sized fish; respectable catch
Fishing term for a fish of satisfying size, or a catch that is considered decent. Often used in angling contexts.
今日は良型のアジが何匹か釣れた。
Today I caught several good-sized horse mackerel.
良型が上がったときはやっぱり嬉しい。
It's really satisfying when you land a respectable catch.
大物 refers to a trophy-sized or exceptionally large fish, while 良型 is more about a decent, satisfying size without necessarily being a record.
Compound of 良 (good) and 型 (shape/size), literally 'good size'. The reading りょうがた is the standard combination; りょうけい is a less common Sino-Japanese reading variant.