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z
English spelling of the IPA z sound: sometimes z (buzz) or x (exist), but usually s (busy).
Words where the IPA z sound is spelled with a z
zero, zebra, zoo, zoological, buzz, fizzy, dizzy, Zulu, zygomatic
dozen, crazy, lazy, dozy, hazy
Words where the IPA z sound is spelled with an s
easy, cosy, user, busy, business
always, does, because, choose, use, close, rose, phase
cousin, design, desire, disease, museum, music, opposite, position, positive, presence, present
Words where the IPA z sound is spelled with an x
exactly, examine, example, executive, exist, exit
Words with a surprise z sound
dissolve, desert, dessert, hussar
xylophone, xenophobic, Xerxes, xiphoid, xerophyte
Plurals and possessives
The rules are the same for saying the plural s (as in "two cats and two dogs)" and the apostrophe s (as in "the cat's bed and the dog's bone" or "cats' and dogs' owners").
If the word ends in a c, f, k, p or t then a plural or apostrophe s makes the IPA s sound (as in "Jack's book" or "the cat's bed"). If the word ends in any other letter, then a plural or apostrophe s makes the IPA z sound (as in "John's book" or "the dog's bed").