Definition of screech. 1  intransitive verb. 2  1 : to utter a high shrill piercing cry : make an outcry usually in terror or pain. 3  2 : to make a shrill high-pitched sound resembling a screech; also : to move with such a sound the car screeched to a stop.  transitive 1  verb. : to utter with or as if with a screech.