Istar noun "Wizard", used of Gandalf, Saruman, Radagast etc. Pl. Istari is attested. Gen. pl. in the phrase Heren Istarion "Order of Wizards" (UT:388). "The istari are translated wizards because of the connexion of wizard with wise and so with witting and knowing" (Letters:207); by this translation Tolkien tries to reproduce the relationship between Quenya istar and ista- #1, 2.
Quenya
istar
proper name. Wizard, (lit.) One Who Knows
Istar
wizard
istari
Istari
The word comes from the verb ista- ("to know"), and possibly the agentive ending -ro.
curuvar
wizard
curuvar _("k")_noun "wizard" (LT1:269 but Gandalf, Saruman etc. were istari)
-on
name
-on gen.pl. ending (3O), in aldaron, aranion, elenion, Eldaron, #esseron, Ingweron, Istarion, Númevalion, Quendion, Silmarillion, Sindaron, tasarion (see Nan-Tasarion), Valion, wenderon, yénion. Normally the ending -on is added to the nominative plural, whether it ends in -i or -r, but some nouns in -ë that would have nominative plurals in -i seem to prefer the ending -ron in the genitive (hence #esseron as the gen. pl. of essë "name", though the nominative pl. is attested as essi and we might have expected the gen. pl. *ession; similarly wenderon, Ingweron).
esse
noun. name
essë
name
essë (1) noun "name", also later name of Tengwa #31, originally (MET) called árë (ázë). (Appendix E). With a pronominal ending esselya "thy name" (VT43:14). Pl. #essi in PM:339 and MR:470, gen.pl. #esseron "of names" in the compound Nómesseron (q.v.); we would rather have expected *ession, given the nom.pl. essi; perhaps #esser is a valid alternative plural form. Essecarmë noun "name-making" (MR:214, 470), Eldarin ceremony where the father announces the name of his child. Essecenta *("k") noun "Name-essay" (see centa) (MR:415); Essecilmë noun "name-choosing", an Eldarin ceremony where a child named him- or herself according to personal lámatyávë (q.v.) (MR:214, 471). The meaning Tolkien originally assigned to the word essë** in the Etymologies was "place" rather than "name" (VT45:12).
essë
noun. name
esta-
verb. name
sairon
wizard
sairon noun "wizard" (SAY); according to LT2:337 and GL:29, Sairon is also the Quenya (or Qenya) name of Dairon (Daeron).
sanda
name
[sanda, sandë] (þ) (2) noun "name" (VT46:16)
sanya
name
[sanya] (þ) (2) noun ?"name" (reading of gloss uncertain, VT46:16)
A name for the five Wizards who travelled from the West to aid the free peoples against Sauron (LotR/1084, UT/388). It usually appeared in its plural form Istari, which meant “those who know” (Let/202, PM/360). Tolkien generally translated the name as “Wizard”, because the Old English sense of word was similar to the true meaning of this Quenya word (Let/207). The name Istar was most likely a combination of the verb ista- “to know” and the old agental suffix -r(o).
The title Istar was not used for ordinary mortal “wizards” or “magicians” (UT/388). For this purpose, perhaps the word [ᴹQ.] sairon was used instead.