To rub the hair thoroughly (while taking a bath) till one feels that one has made his skin wet (underneath the hair) and the one pours water over it

`Aisha said, "Whenever Allah's Messenger (ﷺ) took the bath of Janaba, he cleaned his hands and performed ablution like that for prayer and then took a bath and rubbed his hair, till he felt that the whole skin of the head had become wet, then he would pour water thrice and wash the rest of the body."