Definition

Slang term for someone, typically female, who's being cowardly or acting timid in a situation that calls for courage. It's the kind of insult you'd hear in certain regional dialects.

Example Usage

Don't be such a yatty—just go talk to them if you like them that much.

Source: Urban Dictionary (https://www.urbandictionary.com/define.php?term=yatty&defid=111526)