Welsh comb meaning (informal): definition

Welsh-comb

verbalso spelled Welsh-comb

Etymology Denominal verb of Welsh comb.

Idiomatic, Informal To comb (one's hair) with one's hand.

The intervening years have been kind to Edward Fox and John Wells, who now assume the principal roles, in allowing them to keep their full complement of hair. Mr Fox shows his gratitude by using his rug as a prop, flopping it forward, Welsh-combing it back, letting it stand up on end as if from shock, while Mr Wells is content mostly to let his limply swathe his forehead.1985 July 12, Martin Cropper, “Theatre: The Philanthropist”, in The Times, number 62,188, London, →ISSN, →OCLC, page 15, column 7:
During the applause the singer poured a glass of water from the decanter into the tumbler, drank a mouthful, and Welsh-combed his moustache and hair.2004, Evelyn Conlon, Later On:

1 more example

But her mind couldn’t help dwelling on the way the Russian’s long fingers had Welsh-combed his luxuriant hair.2009, Charlie Brooks, chapter 21, in Citizen, London: Harper, →ISBN, page 145:

noun

Idiomatic One's fingers, used as an improvised method to straighten one's hair.