A simple “Hey, how are you?” is more than enough, and their response can give you an idea of how they're feeling. Unique greetings are fun, but it's probably best to save them for a few calls down the line. People often sound different over the phone, so make sure you tell them who's calling.
If you're in a relationship, it's not unusual to give your partner nicknames, including but not limited to: bae, baby, my love, boo, sweetheart, etc. Turns out these pet names aren't just cute (even though, okay, some might sound silly), they can actually be a super important part of your relationship.
One of the best things that you can call your boyfriend, or even a platonic friend, is handsome. When you call a guy handsome in a romantic relationship, then it makes them feel good about themselves. It also reinforces your relationship because it tells them that you find them physically attractive.
Texting at night may feel a bit more ~intimate~ to you, but don't let that intimidate you. As dating expert Julie Spira previously told Elite Daily, sending messages that suggest familiarly can help deepen your bond with your crush.
In conclusion, if he likes you, he will text you. How guys text you when they like you varies, but some are consistent. For example, a guy will ask many questions about you, text first, compliment you, send emojis, make you laugh, find reasons to talk to you, and give hints for a date.
I don't think there are additional meanings to the term "boyfriend," but a boyfriend could also be called "boo," "beau," "boothang," "main squeeze," "boy," "man," "hubby," and so forth.
The short answer: Though this word was used in the 1500s to refer to sheep sounds, today bae is used as a term of endearment, often referring to your boyfriend or girlfriend.