na-adjective
irresponsible; careless; perfunctory
Negative na-adjective for actions, work, attitudes, or people that are sloppy, unreliable, or done without proper care.
いい加減な人に大事な仕事は任せられない。
You can't entrust important work to an irresponsible person.
店のいい加減な対応に客が怒った。
The customers got angry at the shop's careless service.
na-adjective
half-baked; halfhearted; vague
Used when information, plans, knowledge, explanations, or effort are not properly developed, precise, or committed.
いい加減な知識で説明すると、かえって混乱を招く。
Explaining with half-baked knowledge will only cause more confusion.
彼の説明はいい加減で、肝心な点がはっきりしなかった。
His explanation was vague, and the key points were not clear.
na-adjective, adverb
enough already; cut it out
Used to express irritation or a wish for something to stop, especially in fixed patterns such as いい加減にして and いい加減にしろ.
See also: いい加減にする
冗談はいい加減にして。
Enough with the jokes.
その話はもういい加減にしろ。
Cut it out with that story already.
adverb
Adverbial use meaning something has reached a considerable degree; often conversational and may carry a slight 'by now' or fed-up feeling.
この靴はいい加減古くなってきた。
These shoes have gotten pretty old.
朝から歩きっぱなしで、いい加減疲れた。
After walking nonstop since morning, I'm quite tired.