Adverbial use meaning 'on top of that' or 'to make matters worse'; often used when an additional factor intensifies a situation, frequently in negative contexts.

雨あめが降ふって、余よ計けいに寒さむく感かんじる。
It's raining, which makes it feel even colder.
説せつ明めいを聞きいたら、余よ計けいにわからなくなった。
After hearing the explanation, I became even more confused.

Usage patterns

余よ計けいな〈事こと〉をするto do something unnecessary/uncalled-for
余よ計けいなことをして、かえって迷めい惑わくになった。
I did something unnecessary and it just caused more trouble.
余計よけいな心配しんぱいをするto worry needlessly
母ははは余よ計けいな心しん配ぱいをしてばかりだ。
My mother is always worrying unnecessarily.
〈物もの〉が余よ計けいにあるthere is extra ~ than needed
材ざい料りょうが余よ計けいにあるので、少すこし分わけてあげる。
I have extra ingredients, so I'll give you some.
〈事こと〉で余よ計けいに〈形けい容よう詞し〉になるsomething makes a situation even more ~ than before
薬くすりを飲のんでも治なおらず、余よ計けいに心しん配ぱいになった。

Expressions

余よ計けいなお世せ話わnone of your business; mind your own business; unwanted help

Kanji

余too much, myself, surplus
計plot, plan, scheme

Related words

余よ分ぶんN3sense 1
余計 usually implies unwanted or annoying excess, while 余分 is a neutral term for surplus amount, like extra ingredients.
過か剰じょうN2sense 1
過剰 is a more formal, often technical word for excess (e.g. 過剰生産), whereas 余計 is everyday and often carries a critical tone.
無む駄だN4sense 2
無駄 focuses on something being useless or wasted, while 余計 focuses on something being extra or intrusive beyond what's needed.
不ふ必ひつ要ようN1
余計 describes something excessive or extra beyond what's needed, while 不必要 focuses purely on the absence of necessity.

Opposites

必ひつ要ようN4sense 2
必要 means 'necessary', the direct opposite of 余計's sense of being unnecessary or uncalled-for.

Word family

余よ計けい者もの
unwelcome person; third wheel; interloper · superfluous man (literary archetype)

Written forms

余よ計けいUsage72%
Standard kanji spelling; high-frequency word.
よけいUsage28%
Kana spelling is common in informal writing and when the nuance of 'extra/unnecessary' is emphasized.

Etymology

Compound of 余 (yo, 'surplus') and 計 (kei, 'measure'). The combination conveys the idea of something exceeding the measured amount, hence 'extra' or 'unnecessary'.

The medicine didn't help, and it just made me even more worried.