pretext
/ˈpriːtekst/noun
1- a reason given in justification of a course of action that is not the real reason借口; 托词：
the rebels had the perfect pretext for making their move.
反叛者有最堂皇的借口采取行动。
1.1
- on (或 under)the pretext giving the specified reason as one's justification以…为借口：
he called round on the pretext of asking after her mother.
他以问候她母亲为借口前来拜访。
词源
early 16th cent.: from Latin praetextus 'outward display'， from the verb praetexere 'to disguise'， from prae 'before'+texere 'weave'.