the part of the face below the mouth and above the neck
A strap fastens under the chin to keep the helmet in place. see also double chinIdioms
(keep your) chin up
(informal) used to tell somebody to try to stay cheerful even though they are in a difficult or unpleasant situationChin up! Only two exams left.take something on the chin
(informal)1 to accept a difficult or unpleasant situation without complaining, trying to make excuses, etcIn this business, you have to learn to take criticism on the chin.2 (North American English) to be damaged or badly affected by somethingStockholders took it on the chin yesterday as markets fell sharply.
Usage note: Physical appearanceA person may be described as having:Eyes(bright) blue/green/(dark/light) brown/hazel eyesdeep-set/sunken/bulging/protruding eyessmall/beady/sparkling/twinkling/(informal) shifty eyespiercing/penetrating/steely eyesbloodshot/watery/puffy eyesbushy/thick/dark/raised/arched eyebrowslong/dark/thick/curly/false eyelashes/lashesFacea flat/bulbous/pointed/sharp/snub nosea straight/a hooked/a Roman/(formal) an aquiline nosefull/thick/thin/pouty lipsdry/chapped/cracked lipsflushed/rosy/red/ruddy/pale cheekssoft/chubby/sunken cheekswhite/perfect/crooked/protruding teetha large/high/broad/wide/sloping foreheada strong/weak/pointed/double china long/full/bushy/wispy/goatee bearda long/thin/bushy/droopy/handlebar/pencil moustache/(especially US) mustacheHair and skinpale/fair/olive/dark/tanned skindry/oily/smooth/rough/leathery/wrinkled skina dark/pale/light/sallow/ruddy/olive/swarthy/clear complexiondeep/fine/little/facial wrinklesblonde/blond/fair/(light/dark) brown/(jet-)black/auburn/red/(British English) ginger/grey hairstraight/curly/wavy/frizzy/spiky hairthick/thin/fine/bushy/thinning hairdyed/bleached/soft/silky/dry/greasy/shiny hairlong/short/shoulder-length/cropped haira bald/balding/shaved heada receding hairlinea bald patch/spota side/centre/(US) center (British English) parting/(North American English) partBodya long/short/thick/slender/(disapproving) scrawny neckbroad/narrow/sloping/rounded/hunched shouldersa bare/broad/muscular/small/large chesta flat/swollen/bulging stomacha small/tiny/narrow/slim/slender/28-inch waistbig/wide/narrow/slim hipsa straight/bent/arched/broad/hairy backthin/slender/muscular armsbig/large/small/manicured/calloused/gloved handslong/short/fat/slender/delicate/bony fingerslong/muscular/hairy/shapely/(both informal, often disapproving) skinny/spindly legsmuscular/chubby/(informal, disapproving) flabby thighsbig/little/small/dainty/wide/narrow/bare feeta good/a slim/a slender/an hourglass figurebe of slim/medium/average/large/athletic/stocky build

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