Steve: Darling. Since he is from the old times, he would call you something from the old times.

Tony: Lovebug. He can be such a gentleman but also a big nerd.

Bruce: Honey. When he gets angry, he will call you honey, and then he will calm down right away.

Thor: Princess. He is from a different planet. And somehow they still have royalty there. He treats you like the Princess of Asgard.

Clint: Baby. He loves to be romantic to you. He sometimes calls you Babe.

Natasha: Bae. She is see e tough one so she wouldn't call you something "silly".