keep one's hair on

present singular third person keeps one's hair on · participle present keeping one's hair on · participle past kept one's hair on · past kept one's hair on

1. IrelandUKcolloquialidiomaticTo stay calm; to be patient; to calm down.

   All right, all right, just keep your hair on, mate.

   3 more examples

   “Oh, nothing, nothing!” “Yes, there’s something. I mean to know!” “Keep your hair on; it’s nothing.” “Out with it!” cried Addie, scarlet with rage. And he flew at Jaap’s throat.

   1901, Louis Couperus, translated by Alexander Teixeira de Mattos, Small Souls

   1965 [Chatto & Windus], Margery Allingham, The Mind Readers, 2016, Penguin Random House (Vintage), page 138, ‘Keep your hair on, I don't see any crime. […] ’

   “Sorry old chap—keep your hair on—but surely you knew just about everyone was siphoning off the odd bit, here and there?”

   2014, Melvin Rea, The Island They Towed Away, AuthorHouse, page 233

   Synonyms: keep one's knickers on, keep one's pants on, keep one's shirt on, keep one's wig on