Ghusl (Arabic: غسل ġusl, IPA: [ˈɣʊsl]) is an Arabic term that means the full-body ritual purification which is mandatory before the performance of various Islamic activities and prayers. For any Muslim, it is performed after sexual intercourse (i.e. it is fardh), before Friday prayer and prayers for Islamic holidays, before entering the ihram in preparation for Hajj, after having lost consciousness, and after formally converting to Islam. Sunni Muslims also perform the ablution before Salat al-Tawba "Prayer of Repentance".

Ghusl is often translated as "full ablution", as opposed to the "partial ablution" or wudu وضوء that Muslims perform after lesser impurities such as urination, defecation, flatulence, deep sleep, and light bleeding (depending on the madhhab).

Ghusl is a ritual bath.

Ghusl becomes obligatory for seven causes, and the ghusl for each of these different causes has different names:

In some denominations, two further categories obligate ghusl:

Ghusl also becomes obligatory following a vow or oath to perform it.

Similar to wudu, some water sources are permissible for use for ghusl whereas some water sources are not.

Ghusl requires clean, odourless water that has not been used for a previous ritual and begins with the declaration of the intention of purity and worship.