Green’s Dictionary of Slang

to behave in a deceitful manner.

1897		Witchita Dly Eagle (KS) 5 Sept. 9/5: Sop yo’ just mosey mighty soon / An quit yo’re triflin wid dis coon.
1923		Grainger & Ricketts ‘Triflin’ Blues’ 🎵 Daddy don't you trifle on me / While you’re down in Tennessee.
1978		R.D. Pharr Giveadamn Brown (1997) 30: ‘The boy is trifling. He has to be’.
1971		T.A. Dorsey unpub. ms. q. in Harris Gospel Blues 90: Some woman screams out [...] because some man trifled on her and wounded her to the bone.
2002		Teen Lingo: The Source for Youth Ministry 🌐 triflin v. To cheat on your boy friend or girl friend. ‘Rick! Are you trifflin with Jackie? You better hope Tomeka don’t find out . . . she’ll open up a can on you!’ 2. talking behind a friends back, back stabbing.