Definitions:

1. A pioneering internet company that started as a search engine and web portal. NOUN
   • I used to check my email on Yahoo every day, but now I prefer using Gmail.
2. Used as an exclamation to express excitement, enthusiasm, or triumph. NOUN
   • Yahoo! We finally reached the summit after a challenging hike.
3. Used informally to refer to a rude, uncultivated, or boisterous person. NOUN
   • The party was full of yahoos who were making a lot of noise and causing trouble.

Synonyms:

• hick
• hillbilly
• hoodlum
• hooray
• rube
• woo-hoo
• yippee
• yokel