From Longman Dictionary of Contemporary Englishwigwig1 /wɪɡ/ ●●○ noun [countable] 
DCBartificial hair that you wear on your head → toupéeTHESAURUSwig an object covered with artificial hair that you wear on your headIn England judges still have to wear wigs.Do you think it's real, or is it wig?toupée an area of artificial hair, used to cover a bald part of your headThe singer used to wear a toupée, and then decided to shave all his hair off.hairpiece a wig or a piece of false hair that you wear on your head to make your own hair look thickerUnfortunately the hairpiece didn't quite match the colour of her hair.extensions long pieces of artificial hair that can be attached to your hair to make it look longerI'm thinking of having extensions because my hair gets to a certain length and then becomes so thin that you can see through it.
DCBartificial hair that you wear on your head → toupéeTHESAURUSwig an object covered with artificial hair that you wear on your headIn England judges still have to wear wigs.Do you think it's real, or is it wig?toupée an area of artificial hair, used to cover a bald part of your headThe singer used to wear a toupée, and then decided to shave all his hair off.hairpiece a wig or a piece of false hair that you wear on your head to make your own hair look thickerUnfortunately the hairpiece didn't quite match the colour of her hair.extensions long pieces of artificial hair that can be attached to your hair to make it look longerI'm thinking of having extensions because my hair gets to a certain length and then becomes so thin that you can see through it.Examples from the Corpus
wig• A man in a wig and black robes.• The barristers' wigs were ill-powdered and their curls lacked crispness.• a blond wig• But, with the help of a brown wig, he plays a convincing 30-year-old.• Created by Geno Ventti Long, dramatic wig has been dressed with wax to accentuate curl.• I'd just like to know what he got up to when he took his wig off, that's all!• I slipped my long hair inside the wig, adjusted it, then put on a pair of large sunglasses.• Under their wigs their heads are shaven.wigwig2 verb (wigged, wigging) → wig (somebody) outOrigin wig (1600-1700) periwig type of wig ((16-21 centuries)), from Old French perruque, from Old Italian perrucca “hair, wig” 