noun
plural hairs
[count] :a thin threadlike growth from the skin of a person or animal
[noncount] :a covering or growth of hairs
[noncount] :the covering of hairs on a person's head
[singular] informal :a very small distance or amount
hair of the dog (that bit you)
informal :an alcoholic drink that is taken by someone to feel better after having drunk too much at an earlier time
hide or hair, hide nor hair
in your hair
informal
Someone who is in your hair is bothering or annoying you.
keep your hair on
Brit informal - used to tell someone not to become too excited or upset;
let your hair down
informal :to relax and enjoy yourself
make your hair curl
informal
If something makes your hair curl, it frightens, shocks, or surprises you.
make your hair stand on end
informal
If something makes your hair stand on end, it frightens you.
not have a hair out of place
informal :to have a very neat appearance
not turn a hair
informal :to remain calm even though something frightening or shocking has happened
out of your hair
informal
Someone who is out of your hair is no longer bothering or annoying you.
pull your hair out
or tear your hair out
informal :to be very worried or upset about something
split hairs
to argue about small details or differences that are not important
US