noun
bad food combination; foods that don't go together
Refers to a combination of foods that are traditionally believed to cause digestive problems or illness when eaten together, such as eel and pickled plums, or watermelon and tempura. Often used in the context of folk beliefs about food pairings.
うなぎと梅干しは食い合わせが悪いと言われている。
Eel and pickled plums are said to be a bad food combination.
食い合わせに気をつけて食事を選ぶ。
I choose my meals being careful about bad food combinations.
noun
dovetailing; fitting together
Used for the way parts or schedules fit together neatly, like dovetail joints in woodworking or well-coordinated plans. Less common than the food sense.
この家具は食い合わせがしっかりしていて丈夫だ。
This furniture has tight dovetailing and is sturdy.
予定の食い合わせがうまくいって、効率的に動けた。
The schedules fit together well, and we were able to work efficiently.
Compound of 食い (kui, 'eating', the continuative form of 食う) and 合わせ (awase, 'matching, combining', the continuative form of 合わせる). The food sense likely derives from the idea of 'matching foods' that results in a bad match.