остынь!

calm down! (Damirules); be quiet! (Andrey Truhachev); pipe down! (Taras); calm down (Nansie Lizard); chill! (Ivan Pisarev); take it easy! (Ivan Pisarev); slow down! (Ivan Pisarev); relax! (Ivan Pisarev); cool down! (Ivan Pisarev); chill out! (Ivan Pisarev); unwind! (Ivan Pisarev); chillax! (Ivan Pisarev)

rude

calm your tits! (chilin)

slang

chill out! (Chill the fuck out! • Yeah, well maybe you should chill out. You're going to have a heart attack getting so angry the whole time. Азери); step off (ckasey78)

остынь v

gen.

don't push it

inf.

lighten up (zoologist); cool it (VLZ_58); cool your jets (VLZ_58); chill it (Yeldar Azanbayev)

lit.

keep your shirt on (Artjaazz)

slang

calm one's clams (mancy7)

остыть v

gen.

cool; cool down; cool off; get cool; simmer down; get lukewarm; grow lukewarm; cool one's heels (if someone leaves you to cool your heels, they force you to wait, often until you become calmer "The youths were left to cool their heels overnight in a police cell." Being forced to wait for something КГА); grow cool; become cold (kee46); go cold (They are likely to finish it before their tea goes cold Гевар); get cold

Gruzovik

get cold; grow cool (pf of остывать)

amer.

walk it off (Taras)

animat.

mellow out (Whoa, dude, you need to mellow out! South_Park)

fig.

go off the boil (перестать горячиться • 'You were not – how shall I put it? – in any sense intimate?' 'No, no. Simply on Good-morning-good-morning-lovely-morning- is-it-not terms if I happened to run into her in the street.' 'Nothing more?' 'Nothing more.' I had said the right thing. He went off the boil, and when he next spoke, it was without bulldog and chump chop effects. (P.G. Wodehouse) – он остыл/перестал кипятиться ART Vancouver); of an emotion cool

Gruzovik, fig.

cool down

inf.