take French leave
Verb
Meaning
(intransitive) Synonym of slip out, to leave suddenly without notice or permission.
(intransitive, euphemistic) Synonym of go AWOL, to desert or be temporarily absent from military service without permission.
Source: en.wiktionary.orgSynonyms
awol
abscond
skedaddle
break out
slip away
steal away
vamoose
break loose
pull up stakes
Irish goodbye