arya (1) adj. "excelling", used as the comparative form of mára "good", hence "better" (PE17:57). The superlative ("best") is i arya with the article, with genitive to express *"the best of…" Cf. mára.
Quenya
mára
useful, fit, good
mára
adjective. good, proper, good, proper; [ᴹQ.] useful, fit, good (of things), [ᴱQ.] excellent; mighty, power, doughty
mára
adjective. good
máralë
noun. goodness
mára ná
it is good
mára tyen
good to you, you like
mára tyen
good to you = like
ta mára
so good
arya
excelling
márië
it is good
márië (2) stative verb "it is good" (FS; from mára "good"; however, the stative-verb suffix -ië is hardly valid in LotR-style Quenya)
márië
goodness
márië (1) "goodness", "good" as noun (abstract formation from the adj. mára). (PE17:58, 89). Genitive máriéno, dative máriena, locative máriessë (PE17:59, occurring in the greeting (hara) máriessë "(stay) in happiness", PE17:162) Allative márienna *"to goodness", used as an interjection "farewell" (archaic namárië, q.v.),
alasaila ná lá carë tai mo nave mára
it is unwise not to do what one judges good
carë mára quí tyarë naxa
doing good may cause evil
i mára arano
the good king’s
la navin caritalyas mára
I do not advise you to do so, (lit.) I don’t judge your doing (it) good
lá carita i hamil mára alasaila ná
not to do (in this case) what you judge good (would be) unwise
nás mára nin
I like it
Amarië
good
Amarië fem. name; perhaps derived from mára "good" with prefixing of the stem-vowel and the feminine ending -ië (Silm)
i eru i or ilyë mahalmar ëa
(the one/they) who; (that) which
i (2) relative pronoun "(the one/they) who; (that) which" (both article and relative pronoun in CO: i Eru i or ilyë mahalmar ëa: the One who is above all thrones", i hárar "(they) who are sitting"); cf. also the phrase i hamil mára "(that) which you deem good" (VT42:33). Notice that before a verb, i means "the one who", or, in the case of a plural verb, "those who"; e.g. i carir quettar ómainen "those who form words with voices" (WJ:391). According to VT47:21, i as a relative pronoun is the personal plural form (corresponding to the personal sg. ye and the impersonal sg. ya). This agrees with the example i carir..., but as is evident from the other examples listed above, Tolkien in certain texts also used i as a singular relative pronoun, both personal (Eru i...) and impersonal (i hamil). In the sense of a plural personal relative pronoun, i is also attested in the genitive (ion) and ablative (illon) cases, demonstrating that unlike the indeclinable article i, the relative pronoun i can receive case endings. Both are translated "from whom": ion / illon camnelyes "from whom you received it" (referring to several persons) (VT47:21).
ta
so, like that, also
ta (2) adv. "so, like that, also", e.g. ta mára "so good" (VT49:12)
tai
that which, what
tai (1) pron. "that which, what", "which fact" (VT42:34, VT49:12, 20). The word occurs in the sentence alasaila ná lá carë tai mo navë mára, translated "it is unwise not to do what one judges good". So tai = "what", but it means more literally "that which" (VT49:12), ta + i (cf. ta #1 and the use of i as a relative pronoun). In one note, Tolkien emended tai to ita, reversing the elements (VT49:12) and also eliminating the ambiguity involving the homophone tai #2, see below.
ala-
good
ala- (3), also al-, a prefix expressing "good" or "well" (PE17:146), as in alaquenta (q.v.) Whether Tolkien imagined this ending to coexist with the negative prefix of the same form (#2 above) is unclear and perhaps dubious.
ita
that which
ita 3) pron "that which" (VT49:12), emended from tai (#1, q.v.) The form ita is compounded from the relative pronoun i + the pronoun ta "that, it".
melehta
mighty
melehta adj. "mighty" (PE17:115), cf. meletya
meletya
mighty
#meletya adj. "mighty", isolated from meletyalda adjective with suffix "your mighty" = "your majesty" (see -lda; meletya = *"mighty"). In full Aran Meletyalda "king your mighty" = "your majesty" (WJ:369). Compare melehta.
san
so
san (2) adv. ephemeral word for "so" (ya(n)...san "as...so"; san na "thus be" = let it be so, "amen"); this form was apparently quickly abandoned by Tolkien (VT43:16, 24, VT49.18)
tambë
so
tambë prep. (1) "so" or "as" (referring to something remote; contrast sívë). Sívë...tambë "as...so" (VT43:17).
taura
mighty, masterful
taura adj. "mighty, masterful" (TUR, PE17:115), "very mighty, vast, of unmeasured might or size" (VT39:10). Cf. túrëa.
ter
so
ter (2), also tér, prep. (?) ephemeral word for "so" (see ier), abandoned by Tolkien in favour of tambë (VT43:17)
melehta
adjective. mighty
An adjective for “mighty” derived from the root √MBELEK in a page of notes having to do with “large & small” words, probably from the late 1960s (PE17/115), apparently from the primitive form ✱✶mbelektā (with [kt] > [ht]). A variant form meletya appears with the 2nd-plural possessive suffix -lda as Meletyalda “your mighty” in the Quendi and Eldar essay of 1959-60 (WJ/369), likely from the primitive form ✱✶mbelekya (with [kj] > [tj]). This variant form has a more typical primitive adjective suffix ✶-ya, but is inconsistent with the attested Sindarin cognate S. belaith, so I’d stick with melehta for purposes of Neo-Quenya.
meletya
adjective. mighty
máriën
noun. goodness
mára adj. "useful, fit, good" (of things) (MAG; see MA3; Arct, VT42:34, VT45:30). Nás mara nin "I like it", literally "it is good to me" (VT49:30; read mára for mara?) As the comparative of mára, the unrelated adjective arya "excelling" is used in the sense of "better"; for the superlative *"best", one adds the article: i arya (with genitive to express "the best of…") (PE17:57),