What is "tchick"

Tchick \Tchick\ (ch[i^]k), n. [Imitative.] A slight sound such as that made by pressing the tongue against the roof of the mouth and explosively sucking out the air at one side, as in urging on a horse. -- v. i. To make a tchick.

interj. (Representing this sound.) n. The unilateral palatal click used to urge on a horse. vb. (context intransitive English) to make this sound