Baby is a common English word with multiple meanings:
1. Literally refers to a very young child or infant
2. Term of endearment between romantic partners
3. Slang for something that's easy to do ("This test was a baby!")
4. Used to describe someone who acts immature ("Don't be such a baby!")
5. In music, a common term in song lyrics and titles
6. Can refer to a pet ("How's my baby dog doing?")