二ふた股またをかける

Meanings

1

expression, ichidan verb

cheat on a partner; two-time

idiomatic expression

Specifically refers to being romantically involved with two people at the same time without their knowledge.

彼かれは彼かの女じょに二ふた股またをかけていたことがバレて、振ふられた。
He was found out for two-timing his girlfriend and got dumped.

2

expression, ichidan verb

play both sides; sit on the fence

idiomatic expression

Figurative extension: to try to keep good relations with two opposing parties, or to avoid committing to one side. Less common than the romantic sense.

彼かれは二ふたつの派は閥ばつに二ふた股またをかけて、どちらからも信しん用ようを失うしなった。
He played both factions and lost the trust of both.

Written forms

二ふた股またをかける
Standard kanji spelling using かける in kana.
二ふた股またを掛かける
Alternate kanji spelling with 掛ける; less common but still seen.

Kanji

二two, two radical (no. 7)
股thigh, crotch
掛hang, suspend, depend

Similar words

浮うわ気き
浮気 is a broader term for infidelity or a fling, while 二股をかける specifically means maintaining two concurrent relationships.
二に兎とを追おう
二兎を追う means trying to achieve two things at once (often with the implication of failing at both), while 二股をかける focuses on duplicity in relationships or loyalties.

Etymology

From 二股 (fork, two branches) + を + かける (to hang, to set). The image is of straddling two branches or paths, metaphorically maintaining two relationships or loyalties.