"Crybaby" is the Engpsh equivalent for "爱哭鬼" (ài kū guǐ) in Chinese.
It's an informal term and it is used to refer to someone who cries easily or excessively. The phrase comes from the idea of the person being pke a baby who cries a lot.
Examples:
"He's such a crybaby, he cries at every pttle thing."
(他是个爱哭鬼，每件小事都会哭。)
"Don't be such a crybaby, you're making me uncomfortable."
(不要像个爱哭鬼，你这样让我很不舒服。)
"She's not a crybaby, she just gets emotional easily."
(她不是爱哭鬼，她只是容易感情化。)