Dry, waterless, ablution.

Dry purification when water is not available or is detrimental to health.

a ritual washing that can be carried out by those too weak or bed-bound for a normal wudu. Symbolic hand gestures and the use of a stone or clean dust instead of water mean that tayammum can be performed by almost anyone. The patient touches the stone or dust with both hands and then moves the hands over the face, hands and forearms. Tayammum can also be used in dire circumstances when fresh, clean water is not available.

the purification with dry earth preparatory for the prayer done in place of wudu when the latter is not possible.

substitution for wudu' and/or ghusl.

Tayammum refers to the dry ablution in Islam using sand or dust, which may be performed in place of wudu or ghusl, only if no clean water is readily available.