noun
1
BAD : He had a black hair and very clear eyes.
GOOD : He had black hair and very clear eyes.
BAD : Her beautiful blond hairs were shining in the sun.
GOOD : Her beautiful blond hair was shining in the sun.
◆◆◆
When you mean 'a single hair' or 'several individual hairs', hair is a countable noun: 'There was a long black hair in my soup.' 'Stand still and I'll brush the hairs off your jacket.'
When you mean 'all the hair on a person's head', hair is uncountable: 'Where do you go to have your hair cut?'
2
See CUT 4 (↑ cut )