buy into

phrasal verb
1
to buy shares in a company, especially in order to gain some control over it
سرمایه‌گذاری کردن در, سهام‌خریداری کردن
2
to believe something, especially an idea that many other people believe in
باور کردن, پذیرفتن, قبول کردن
She had never bought into the idea that to be attractive you have to be thin.
related noun buy-in