Traditionally, all Hindus kept a tuft or lock of hair (Sanskrit : Sikha; Malayalam : Kuduma) on their head. Not to keep one was contrary to conventions and even considered impious. Namboothiris were supposed to have a four "Viral" or finger (about 6.5 cm) diameter round tuft on the top of the head, with a four finger gap above the hair line on the forehead. If bald in that area, it could be grown on the left or right side, or wherever possible.

Tamil Braahmanans kept the tuft at the back of the head. Embraanthiris {Tulu Braahmanans) had an 8-Viral (about 13 cm) round tuft with a gap of 8-Viral from the hair line.

Customarily, Namboothiris should keep the tuft knotted and ordinarily kept straight up always, except during drying, say after bath. There was a slight "Asudhhi" (defilement), called "Kaal Kazhukaa Sudhham", if it is purposely or even inadvertantly untied. One had to perform "Kaal Kazhukal" ("Paadaprakshaalanam" - washing the feet) to remove this Asudhhi. The tuft was actually not tied into a knot, but rather twisted ("Pirichidal") which is what Brahmachaaris ("Upanichunnis") compulsorily did.

Some Namboothiris used to tie the tuft except during "Sraadhham" (death anniversary ritual) and related ceremonies, when it had to be only twisted and let the bunch fall to the left side. During other religious functions such as Pooja, it was knotted and let fall to the right.