Wiktionary
dawah
n. An Islamic form of proselytism.
WordNet
dawah
n. missionary work for Islam [syn: da'wah]
Wikipedia
Dawah
(also transliterated daawa(h); "invitation") means the proselytizing or preaching of Islam. Da‘wah literally means "issuing a summons" or "making an invitation", being a gerund of a verb meaning variously "to summon" or "to invite" (whose triconsonantal root is d-ʕ-w ). A Muslim who practices da‘wah, either as a religious worker or in a volunteer community effort, is called a (, plural / ).
A dā‘ī is thus a person who invites people to understand Islam through dialogue, not unlike the Islamic equivalent of a missionary inviting people to the faith, prayer and manner of Islamic life.