adj.

flirt (often with with; to behave (towards someone) as though one were in love but without serious intentions • She flirts with every man she meets); dally; toy; play around; play about; play; play footsie; make love to; coquet; gallant (with); philander; gallivant; play the wanton (PanKotskiy); chat up (Elena102)

amér.

make a pass (Nevtutor); make a play (Bonikid); make time with (someone – с кем-либо VLZ_58); make a play for (Aly19)

arg.adolesc.

rizz up (с кем-л. -- with smbd Ремедиос_П)

argot.

dilly-dally; flam; gam; mash; mack (Alexey Lebedev); give the come-on (Buddy89); calico; cake (без серьёзных намерений – to flirt with no inentions of getting serious Franka_LV)

idiom.

get fresh (To flirt. Interex)

inform.

carry on with; make up to (alia20); play about with (Пчёлка_83); hit on; carry on (with); hit on girls (george serebryakov); lead somebody on (с кем-либо; и при этом не любить этого человека; She led me on and then dumped me. – Она пофлиртовала со мной и потом бросила. TarasZ); dally (with Andrey Truhachev); mess with (to engage romantically with someone • Now you're messing with (a son of a bitch) – Сейчас ты мутишь с (каким-то ублюдком) Nazareth, Hair of the dog