vocal tic

vocal-tic的词性：
n.（名词）

1. An involuntary, abrupt, and inappropriate grunt, bark, or other exclamation or utterance, occurring especially in Tourette's syndrome.
哼哼声：一种不自觉的、突然的和异常的咕哝声、吼叫或其它的叫喊或发声，尤指出现于图雷特综合症中