Pronunciation guide: IPA symbols, stress and word endings

Vowels

iː	see	ɪ	sit	e / ɛ	bed	æ	cat
ɑː	father	ɒ	hot (UK)	ɔː	law	ʊ	put
uː	too	ʌ	cup	ɜː	bird	ə	about
eɪ	day	aɪ	my	ɔɪ	boy	aʊ	now
əʊ / oʊ	go (UK / US)	ɪə	near	eə	hair	ʊə	tour

Consonants that look unusual

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.

Marks

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)

Common word endings

-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.

English Dictionary · 107,383 entries · Sources & licences

valency

/ˈveɪ.lən.si/ noun

Also a form of valence

Forms valencies

noun (uncountable, by extension) The capacity of something to combine with other things, as for example the capability of a vaccine as measured by the number of pathogen serotypes that it can counteract. “vaccine valency”
noun (countable, graph theory) The number of edges connected to a vertex in a graph.
noun (uncountable) Importance, significance.

Synonyms

degree valence

Etymology

From Late Latin valentia and Latin valentia (“bodily strength; health; vigour”) + English -y (suffix forming abstract nouns denoting a condition, quality, or state). Valentia is derived from valēns (“healthy, strong, vigorous”) + -ia (suffix forming feminine abstract nouns); while valēns is the present active participle of valeō (“to be healthy, sound, or well; to be strong; to have influence or power, etc.”), ultimately from Proto-Indo-European *h₂welh₁- (“to rule; powerful, strong”).
Sense 1 (“combining capacity of an atom”) and sense 3 (“number of arguments a verb can have”) are possibly from valence + -y.

Sources: Wiktionary · WordNet 3.0 — from the Wiktionary entry “valency”, CC BY-SA 4.0. Details