stick-in-the-mud
noun
Meaning
A person who is unwilling to try new things or participate in exciting activities.
Examples
- Don't be such a stick-in-the-mud; come join us for karaoke tonight.
- She felt like a stick-in-the-mud because she preferred reading at home to going to loud parties.
Synonyms: prude, killjoy, fuddy-duddy, party pooper