expression
on the pretext of; under the guise of
Fixed expression used to indicate that something is done using a stated reason as an excuse or cover. Often followed by a verb phrase describing the real action.
彼は仕事に事寄せて、会合を欠席した。
He skipped the meeting on the pretext of work.
病気にことよせて、学校を休んだ。
I stayed home from school under the pretext of being sick.