Safavid
The term "Safavid", as in Safavid Dynasty (of which Sheikh Safi is the Eponym), is likewise referred to as "Safavi" by Persian speakers. The "d" at the end of "Safavid" was added by the principle of analogy with the Greek-derived names of several ancient dynasties, such as the Achaemenid dynasty and the Sassanid dynasty, based on the oblique cases of the Greek names. The English adjective "Safavid" and the name "Safavids" for the dynasty, and the corresponding forms in many European languages, are therefore based on a redundant application of adjective-forming rules.
The names "Safavid/Safavids" are well-established in the English language, however, and have become legitimate terms. When added to a Shah's name however, the original "Safavi", without the "d" at the end, must always be retained, e.g., Shah Ismail I Safavi.
There was a brach of the Safavi Family (direct descendants of Shah Abbas) that settled in parts of Northern and Central India under the titles "Abbasi" and "Alavi".
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