dummy up

to stop talking all of a sudden the suspect just dummied up and demanded the presence of an attorney Synonyms belt up [British], clam up, dry up, shut up, hush, pipe down, quiet (down)Related Words calm (down), cool (down), settle (down); haw, hemNear Antonyms pipe up, sound off, speak out, speak up, spout (off), talk upAntonyms speak, talk