IPA: //ˈbɔɪfrɛnd//
KK: /ˈbɔɪˌfrɛnd/
A male partner in a romantic relationship or a close male friend.
She introduced her boyfriend to her family at dinner.
Boyfriend is formed from "boy" (from Old English "bōia", meaning a young male) and "friend" (from Old English "freond", meaning a person with whom one has a bond of mutual affection). The word "boyfriend" refers to a young male who is a friend, typically in a romantic context.
Think of a 'young male' ('boy') who is also a 'friend' — that's what a boyfriend is, someone you have a special bond with.