Pronunciation guide: IPA symbols, stress and word endings

θ	thin	ð	this	ʃ	she	ʒ	measure
tʃ	church	dʒ	judge	ŋ	sing	j	yes

p b t d k g f v s z h m n l r w sound as in ordinary English spelling.

ˈ main stress, before the stressed syllable: /ˈwɔːtə/ water · ˌ lighter (secondary) stress: /ˌʌndəˈstænd/ understand
ː a long vowel · (r) an r said only in accents that pronounce it (most American, Scottish, Irish)

-s / -es (plurals; he/she form of verbs): /s/ after voiceless sounds (cats), /z/ after voiced (dogs), /ɪz/ after s, z, sh, ch, j sounds (buses, watches). Spelling: -es after s, x, z, ch, sh; consonant + y → -ies (city → cities).
-ed (past): /t/ after voiceless sounds (walked), /d/ after voiced (played), /ɪd/ after t or d (wanted). Spelling: love → loved, stop → stopped, carry → carried.
-ing: make → making, run → running, see → seeing.
Irregular: go, went, gone · be, was, been · see, saw, seen · man → men · child → children · mouse → mice.
Older (King James) forms: -eth = -s (he loveth = he loves) · -est with “thou” (thou lovest) · spake = spoke.

grammatical

/ɡɹəˈmæt.ɪ.kəl/ adjective

adjective Not breaching any constraints of the grammar, or morpho-syntax, of the relevant language. “Your writing in English is not grammatical enough for publication, so we will hire an editor to fix it where necessary while preserving the intended meaning.”
adjective Of or pertaining to grammar. “The writing was measured for both grammatical complexity and accuracy factors.”

Synonyms

From Middle French grammatical, from Latin grammaticālis.

adjective Of or pertaining to grammar; of the nature of grammar; as, a grammatical rule.
adjective According to the rules of grammar; grammatically correct; as, the sentence is not grammatical; the construction is not grammatical. -- Gram*mat"ic*al*ly, adv. -- Gram*mat"ic*al*ness, n.

Etymology [L. grammaticus, grammaticalis; Gr. grammatical. See Grammar.]

Sources: Wiktionary · WordNet 3.0 · Webster’s 1913 — from the Wiktionary entry “grammatical”, CC BY-SA 4.0. Details

Sanskrit dictionary entries whose meaning includes “grammatical” (best matches first).

औज्जिहायनक aujjihāyanaka name of a grammatical school.
रौढीय rauḍhīya name of a grammatical school.
सङ्ग्रह saṅgraha name of a grammatical work by Vyāḍi.
प्रत्ययलोप pratyaya-lopa elision of a grammatical affix or suffix.
चैत्रकूटी caitrakūṭī title of a commentary on a grammatical work.
सावग्रह sāvagraha having the grammatical mark called Ava-graha, q.v.
अनुषञ्जन anu-ṣañjana connection with what follows, concord; grammatical relation.
उपलेख upalekha title of a grammatical work connected with the Prātiśākhyas.