SEX/HAVE SEX WITH literary a sexual relationship, especially a secret one 风流韵事，〔尤指〕偷情
Examples from the Corpus
amour• Leaving her amour with strict instructions on how to find her, she retired to bed and waited.• I wish them a night as perfect as ours, mon amour.• Just today one of the missionary school youth was about to elope with his new amour.