hairwash

noun2

1. •
   The act of washing the hair on a person's head.

   • I had a hairwash today and the barber came and cut my nails. — 2014
2. •
   A preparation used for washing the hair on a person's head: shampoo or similar.

   • Chokecherry bark […] A hairwash to strengthen the hair and encourage growth. — 2012