哑语

sign language

(onom.) sound of cawing / sound of infant learning to talk / variant of 呀[ya1]

dumb / mute / hoarse / husky / unexploded (of artillery shell etc)

mute; dumb; incapable of speech / (of a voice) hoarse; husky / (of a bullet, bomb etc) dud

dialect / language / speech

to tell to

to use sign language