(ほんき)にする

ほんきにする
expression
to take seriously; to believe (something said in jest)
1. to take seriously; to believe; to take at face value
To treat something said — often a joke, exaggeration, or casual remark — as if it were genuinely meant. Frequently used when someone mistakenly believes something that was not intended seriously.
冗談(じょうだん)本気(ほんき)にするな。
Don't take the joke seriously.
(かれ)(わたし)(うそ)本気(ほんき)にした。
He actually believed my lie.
適当(てきとう)()っただけなのに、本気(ほんき)にしないでよ。
I just said it offhandedly — don't take it seriously.

Composed of 本気(ほんき) (seriousness, earnestness) + にする (to treat as, to make into). The expression focuses on the listener's interpretation: treating something as serious or true.

USAGE:
Often used in the negative imperative 本気(ほんき)にするな / 本気(ほんき)にしないで (don't take it seriously). Distinct from 本気(ほんき)()す (to get serious, to give it one's all), which is about one's own effort rather than interpreting someone else's words.

COMMON COLLOCATIONS:

  • 冗談(じょうだん)本気(ほんき)にする — to take a joke seriously
  • 本気(ほんき)にしないで — don't take it seriously
  • 本気(ほんき)にされる — to be taken seriously (passive)
  • (うそ)本気(ほんき)にする — to believe a lie

SIMILAR WORDS:

  • ()()ける — to take at face value (very similar; slightly more formal)
  • (しん)じる — to believe (neutral; broader usage)
  • 本気(ほんき)()す — to get serious, to give it one's all (different meaning: about effort, not belief)