Elendil masc. name"Star-friend", "Lover or student of stars", applied to those devoted to astronomical lore. However, when the Edain used this name they intended it to mean "Elf-friend", confusing elen "star" and elda "elf" (WJ:410). (This idea that the name was misapplied seems to be late; Tolken earlier interpreted the name as an ancient compound Eled + ndil so that the meaning really was "Elf-friend"; see Letters:386. See also NIL/NDIL in the Etymologies, where Elendil is equated with "Ælfwine", Elf-friend.) Allative Elendilenna "to Elendil" (PM:401); Elendil Vorondo genitive of Elendil Voronda "Elendil the Steadfast" _(CO) Pl. Elendili the Númenórean Elf-friends (Silm)_; the variant Elendilli in SD:403 would seem to presuppose a stem-form Elendill- not attested elsewhere. Tar-Elendil a Númenorean king, UT:210.
Quenya
elendil
masculine name. Elf-friend, Star-lover
Elendil
star-friend
elendilmir
proper name. Star of Elendil
elendil’s oath
Elendil’s Oath
Elendil’s oath made upon arriving in Middle-earth, repeated by Aragorn when he assumed kingship of Gondor (LotR/967).
elendili
collective name. Elf-friends
Eldandil
elf-friend
Eldandil (pl. Eldandili in WJ:412) noun "Elf-friend" (by the Edain confused with Elendil, properly "Star-friend") (WJ:410)
eldandil
masculine name. Elf-friend
quendil
masculine name. Elf-friend
Quendendil
elf-friend
Quendendil (also contracted Quendil; pl. Quendili in WJ:410) masc. name "Elf-friend" (WJ:410)
Elendil
Devoted to the Stars
Elendil's name actually means "Devoted to the Stars" in Quenya.
For the Dúnedain it was intended to signify "Elf-friend" (Adûnaic Nimruzîr), since they tended to confuse the Quenya element EL for both "Elf" and "star".
-dil
-wine
-dil, -ndil, ending that Tolkien likened to Old English "-wine", sc. "-friend" as part of names, e.g. Elendil, Eärendil (NIL/NDIL); see the entry -ndil. Also long -dildo (VT46:4), and possibly -(n)dilmë as the corresponding feminine form (see Vardilmë).
Elessar
elf-stone
Elessar masc. name "Elf-stone" (Elen + sar, actually "Star-stone", cf. Elendil concerning elen "star" being used to mean "Elf") (LotR3:V ch. 8). Genitive Elesarno _(VT49:28, read _Elessarno?) indicates that the stem is -sarn-. As a common noun, elessar or "elf-stone" may signify "beryl" (in the chapter Flight to the Ford in the LotR, Aragorn finds "a single pale-green jewel" and declares: "It is a beryl, an elf-stone"). Elessar as a name may also be seen as a pun or variant of Elesser "Elf-friend".
voronda
steadfast in allegiance, in keeping oath or promise, faithful
voronda adj. "steadfast in allegiance, in keeping oath or promise, faithful", used as a title of Elendil Voronda "Elendil the Faithful"; genitive Vorondo in CO. Only glossed "faithful" in LT1:250.
-nna
to, at, upon
-nna "to, at, upon", allative ending, originating from -na "to" with fortified n, VT49:14. Attested in cilyanna, coraryanna, Endorenna, Elendilenna, númenórenna, parma-restalyanna, rénna, senna, tielyanna, q.v. If a noun ends in -n already, the ending -nna merges with it, as in Amanna, formenna, Elenna, númenna, rómenna as the allative forms of Aman, formen, elen, númen, rómen (q.v.). Plural -nnar in mannar, valannar, q.v.
-nil
-wine
-nil, final element in compounds, similar in meaning to Old English "-wine", sc. "-friend" as an element in names (NIL/NDIL). Also long -nildo (VT46:4). Variant of -ndil. In Eärnil, contraction of Earendil.
-nna
to
-n (1) dative ending, originating as a reduced form of -nă "to", related to the allative ending -nna (VT49:14). Attested in nin, men, ten, enyalien, Erun, airefëan, tárin, yondon (q.v.) and also added to the English name Elaine (Elainen) in a book dedication to Elaine Griffiths (VT49:40). The longer dative ending -na is also attested in connection with some pronouns, such as sena, téna, véna (q.v.), also in the noun mariéna from márië "goodness" (PE17:59). Pl. -in (as in hínin, see hína), partitive pl. -lin, dual -nt (Plotz). The preposition ana (#1) is said to be used "when purely dative formula is required" (PE17:147), perhaps meaning that it can replace the dative ending, e.g. *ana Eru instead of Erun for "to God". In some of Tolkiens earlier material, the ending -n (or -en) expressed genitive rather than dative, but he later decided that the genitive ending was to be -o (cf. such a revision as Yénië Valinóren becoming Yénië Valinórëo, MR:200).
ana
to
ana (1) prep. "to" (VT49:35), "as preposition _ana _is used when purely _dative formula is required" (PE17:147), perhaps meaning that the preposition ana can be used instead of the dative ending -n (#1, q.v.) Also as prefix: ana- "to, towards" (NĀ1); an (q.v.) is used with this meaning in one source (PE17:127)_
na
to, towards
na (2) prep. "to, towards", possibly obsoleted by #1 above; for clarity writers may use the synonym ana instead (NĀ1). Originally, Tolkien glossed na as "at, by, near"; the new meaning entered together with the synonyms an, ana (VT45:36).
vórima
steadfast in allegiance, in keeping oath or promise, faithful
vórima (more or less identical to vorima above?) adj. "steadfast in allegiance, in keeping oath or promise, faithful"; genitive vórimo in a variant of CO; see UT:317. In VT45:7, vórima is glossed "continuous, enduring, repeated".
Tar-Elendil was the fourth ruler of Númenor (UTI/219). Many centuries later a second, more famous, Elendil became the leader of the Men of the West against Sauron at the end of the Second Age and was considered the first king of Gondor and Arnor (LotR/1037). This name is attributed two different meanings: “Elf-friend” and “Star-lover” (WJ/410). The first interpretation was common among Men, and was derived from the ancient associations between Elda “Elf” and †él “star”. Properly speaking, though, his name was a compound of elen “star” and the suffix -(n)dil “lover”, so “Star-lover” is a better interpretation in proper Quenya. The proper Quenya for “Elf-friend” would be Eldandil.
Conceptual Development: In the very first draft of the tale of the Fall of Númenor, this character was named N. Agaldor > N. Amroth (LR/12, 31). When this character first appeared in the “Lost Road”, his name was ᴹQ. Herendil “Fortune’s Friend” and his father was called ᴹQ. Elendil (LR/57). In “The Notion Club Papers”, the character was given the Adûnaic name Ad. Nimruzân >> Nimruzîr “Elf-friend” (SD/389-90), and his contemporaneous Quenya name also shifted to ᴹQ. Elendil (SD/356). His father became ᴹQ. Amardil, later Q. Amandil.
The earlier character Ælfwine might be consider a precursor to Elendil, at least in the meaning of his name: “Elf-friend”. Therefore, the Early Qenya name ᴱQ. Eldairon of Ælfwine could be considered a precursor to the name Elendil (LT2/313).