boyfriend: hey, wanna go to the movies with me later?  you: oh my gosh i'm sorry maybe tomorrow i've got plans with my bestie already
an adoring nickname for one you hold in highest esteem, more commonly known as a best friend
"boyfriend: hey, wanna go to the movies with me later?  you: oh my gosh i'm sorry maybe tomorrow i've got plans with my bestie already" What is the definition of "bestie"?