Definition
To suddenly become extremely angry.
How People Actually Use It
A contraction of "flare-up" and "flaming" (as in homosexual). Briefly becoming very attracted to the same sex, perhaps only while under the influence of drugs or alcohol. In other words, a straight person having a gay moment, or a gay person having an EXTRA-gay moment.
"Girl A: "I thought Emma was here with Dave." Girl B: "She is." Girl A: "Then why is her tongue down Megan's throat?" Girl B: "Oops - looks like another flame-up. She had one of those at last year's sorority mixer.""
Source: Urban Dictionary