Buy in has 3 different meanings across 1 category:
Verb
Noun
1
Alternative spelling of buy-in
Verb
1
amass so as to keep for future use or sale or for a particular occasion or use
"let's stock coffee as long as prices are low"
2
To accept an idea as valid; to join in on a concept.
Broader Terms (hypernyms)
Narrower Terms (hyponyms)