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彼は仕事をいい加減にやるので、上司に怒られた。
He did his work irresponsibly, so his boss got angry.
lacking care or attention to detail; irresponsible in one's duties or behavior
いい加減な態度で接客するな。
Don't serve customers with such a careless attitude.
彼はいい加減な約束しかしない。
He only makes half-hearted promises.
Often used to criticize someone's lack of seriousness or reliability.
moderate; appropriate; reasonable (in a neutral sense)
いい加減な塩加減が料理の美味しさを左右する。
The right amount of salt greatly affects the taste of the dish.
This meaning is less common and often requires context to distinguish from the primary definition.
quite; rather; pretty (colloquial intensifier)
いい加減疲れた。
I'm pretty tired.
Used to emphasize a state or feeling, similar to かなり (kanari).
The word いい加減な can mean 'irresponsible' or 'moderate' depending on context. Pay attention to tone and accompanying words to distinguish the meaning.
The primary meaning of いい加減な is negative (irresponsible). Using it to mean 'moderate' in formal contexts may be misunderstood.
Combination of いい (good/okay) and 加減 (moderation/adjustment). Originally meant 'moderate' or 'balanced,' but evolved to imply 'careless' or 'irresponsible' due to negative connotations in usage.
The primary meaning is negative, implying a lack of responsibility or care. Be cautious when using the neutral sense (moderate/appropriate), as it is less common and may cause confusion. The colloquial intensifier usage is very informal.