Its Definition:

Literally: Siwak as a verb is to rub.

As a noun, it is the stick used to brush one's teeth with.

It is also called miswak.

Legally: Siwak is using a twig, or the like or indeed anything rough [In which case a toothbrush applies] , in rubbing the teeth and the surrounding gums.

It is best performed using something hard which has been moistened with water.

It is best to use arak then palm twigs, then pomegranate twigs, for what Abu K Hayra Al-Sabahi (G. p. H) narrated:

"I was with the delegation who came to the Prophet (P. B. U. H) and he supplied us with twigs from arak tree to make siwak with.

[Narrated by Al-Tabarani in Al-Kabir, Majma' Al-Zawa'ed (The Collection of Supplements), Vol. 2, page 100].

Second in place is palm tree then pomegranate tree.

Al-Mutwalli said: "It is recommended to be performed with a fragrant stick".