Webster's Revised Unabridged Dictionary · 1913

Shampoo

Shampoo , transitive verb

[Hind. chāmpnā to press, to squeeze.]

1.
To press or knead the whole surface of the body of (a person), and at the same time to stretch the limbs and joints, in connection with the hot bath.
2.
To wash throughly and rub the head of (a person), with the fingers, using either soap, or a soapy preparation, for the more thorough cleansing.

Shampoo , noun

The act of shampooing.