have an affair

English

have an affair (third-person singular simple present has an affair, present participle having an affair, simple past and past participle had an affair)

To engage in a romantic or sexual relationship while being married. (This entry is a translation hub.)

engage in a relationship while married

Chinese:
Mandarin: 有外遇 (yǒu wàiyù), 有染 (zh) (yǒurǎn) (literary), 胡搞 (zh) (húgǎo), 戀愛 / 恋爱 (zh) (liàn'ài), 相好 (zh) (xiānghǎo), 偷腥 (zh) (tōuxīng), 有一腿 (zh) (yǒuyītuǐ), 有一手 (yǒuyīshǒu), 偷老婆 (tōu lǎopó) (with somebody's wife)
Dutch: vreemdgaan (nl), uitlopen (nl) (Suriname)
Finnish: olla suhde (subject in the adessive case), olla suhteessa, pettää (fi) (cheat on)
German: eine Affäre haben
Hungarian: viszonya van
Japanese: 浮気する (ja) (うわきする, uwaki suru), 不倫をする (ja) (ふりんをする, furin o suru)
Korean: 불륜하다 (bullyunhada), 정부를 두다 (jeongbureul duda), 관계를 갖다 (gwan'gyereul gatda), 바람을 피우다 (barameul piuda)
Polish: romansować (pl) impf, flirtować (pl) impf
Portuguese: ter um caso
Russian: име́ть рома́н impf (imétʹ román), име́ть любо́вную связь impf (imétʹ ljubóvnuju svjazʹ), крути́ть аму́ры impf (krutítʹ amúry), изменя́ть (ru) impf (izmenjátʹ), измени́ть (ru) pf (izmenítʹ), (intransitive) гуля́ть (ru) impf (guljátʹ)
Spanish: tener una aventura, tener un desliz, tener un amorío, ser infiel