look up any word, like half chub:
 
1.
when a male is sexually attracting the opposite sex by flirting with them.
yo I was macin so many bitties last night

I was macin on a shit load of bitties at that rad party
by jsucker56 November 29, 2009
 
2.
An intimate interacial relationship between a man and woman
Look at Dawyne over there with Samantha, dude he's macin
by BMoney January 27, 2005
 
3.
1. When using any Apple product

2. When eating a Big Mac from McDonald's
1. Dude, Mike got a Mac Pro.

Yeah he's seriously gonna be Macin'

2. Wow, she ordered three Big Mac's.

Yep she's Macin'
by The Asian Hindu February 14, 2011