noun
failure; unpopularity; lack of success
Refers to something that does not go well, is not well received, or fails to gain popularity. Often used for events, products, or performances that flop.
新作映画は不当たりに終わった。
The new movie ended up being a flop.
あの店は不当たりで、すぐに閉店した。
That shop was unpopular and closed down quickly.
不評 means 'bad reputation' or 'unfavorable criticism', while 不当たり focuses on the result of being unsuccessful or unpopular.
失敗 is a general word for 'failure' or 'mistake', whereas 不当たり specifically implies lack of success or popularity in a public or commercial context.
Compound of 不 (fu, 'not') + 当たり (atari, 'hit, success'). The exact historical derivation is uncertain, but the word follows a common pattern of negating a noun with 不.