Meaning of the word "long in the tooth" in English

What does "long in the tooth" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

long in the tooth

US /lɔŋ ɪn ðə tuθ/
UK /lɒŋ ɪn ðə tuθ/

Idiom

old or rather old

Example:
He's a bit long in the tooth to be starting a new career.
This car is getting a bit long in the tooth, I think it's time for a new one.