Real Dictionary

crybaby
countable noun: If someone calls a child a crybaby, they mean that the child cries a lot for no good reason.

crybaby in American English
a person, esp. a child, who cries often or with little cause
intransitive verb: to cry or complain easily or often
noun: a person, esp. a child, who cries readily for very little reason

crybaby in British English
noun: a person, esp a child, given to frequent crying or complaint