A hookah (Hindustani: حقّہ (Nastaleeq), हुक़्क़ा (Devanagari), IPA: [ˈɦʊqːa]; also see other names), shisha, or waterpipe is a single- or multi-stemmed instrument for heating or vaporizing and then smoking either tobacco, flavored tobacco (often muʽassel), or sometimes cannabis, hashish and opium. The smoke is passed through a water basin—often glass-based—before inhalation.

The major health risks associated with smoking tobacco, cannabis, opium and other drugs through a hookah include exposure to toxic chemicals, carcinogens and heavy metals that are not filtered out by the water, alongside those related to the transmission of infectious diseases and pathogenic bacteria when hookahs are shared. Hookah and waterpipe use is a global public health concern, with high rates of use in the populations of the Middle East and North Africa as well as in young people in the United States, Europe, Central Asia, and South Asia.

The hookah or waterpipe was invented by Abul-Fath Gilani, a Persian physician of Akbar, in the Indian city of Fatehpur Sikri during Mughal India; the hookah spread from the Indian subcontinent to Persia first where the mechanism was modified to its current shape and then to the Near East. Alternatively, it could have originated in the Safavid dynasty of Persia, from where it eventually spread to the Indian subcontinent.

Despite tobacco and drug use being considered a taboo when the hookah was first conceived, its use became increasingly popular among nobility and subsequently widely accepted. Gradually, burned tobacco has been commonly replaced by vaporizing flavored shisha. Still the original hookah is often used in rural South Asia, which continues to use Tumbak (a pure and coarse form of unflavored tobacco leaves) and smoked by burning it directly with charcoal. While this method delivers a much higher content of tobacco and nicotine, it also incurs more adverse health effects compared to vaporized shisha hookahs.

The word hookah is a derivative of "huqqa", a Hindustani word, of Arabic origin (derived from حُقَّة ḥuqqa, "casket, bottle, water pipe"). Outside its native region, hookah smoking has gained popularity throughout the world, especially among younger people.