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.

acuity

/əˈkjuːɪti/ noun

Forms acuities

noun Sharpness or acuteness, as of a needle, wit, etc.
noun (figurative) The ability to think, see, or hear clearly. “The old woman with dementia lost her mental acuity.”

Synonyms

From Middle English acuite, acuyte, from Middle French acuité, from Medieval Latin acuitas, irreg., from Latin acuō (“sharpen”).

Etymology [LL. acuitas: cf. F. acuité.]

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