n. pl. Mah·dis
a. The messiah prophesied to appear at the world's end and establish a reign of peace and righteousness.
b. In Twelver Shia belief, the 12th imam, who is expected to emerge from occultation to fulfill this role.
2. A person who claims to be or is seen as the messiah.
[Arabic mahdī, rightly guided one, Mahdi, passive participle of hadā, to lead; see hdy in the Appendix of Semitic roots.]
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