Download
← All posts

box is /ks/, exam is /gz/, xylophone is /z/ — How Many Ways Can One Letter Be Said?

Most learners treat the letter X as one fixed sound — the "ks" in box. Then exam shows up voiced as /gz/, xylophone starts with a plain /z/, and anxious somehow turns into /kʃ/. Same letter, four different sounds, and the spelling gives no warning about which one you're looking at.

The good news: none of this is random. What comes right before and after the X tells you almost everything.

Case 1: /ks/ — the default, and always the case before a consonant

This is the sound most X's actually make.

Notice that last group: whenever the letter right after X is a consonant (the p in expensive, the t in extreme), X stays voiceless /ks/ no matter where the stress falls. No exceptions here.

Case 2: /gz/ — "ex" followed by a stressed vowel

When the letter after X is a vowel, and the syllable right after it is stressed, X voices to /gz/.

The h in exhibit is silent, so it behaves the same as "ex + vowel." In every one of these, the stress lands on the syllable right after "ex," not on "ex" itself.

Compare: why does exit stay /ks/?

exit /ˈeksɪt/, exercise /ˈeksəsaɪz/, excellent /ˈeksələnt/ — here the stress sits on "ex" itself, and the syllable after it is unstressed, so X keeps its voiceless sound.

The shortcut: stressed syllable right after X → it voices to /gz/. Unstressed syllable right after → it stays /ks/.

Case 3: /z/ — a handful of Greek-origin words starting with X

When a word actually starts with the letter X, it's almost always a Greek loanword, and it's read as /z/.

There aren't many of these, so once you know the rule, word-initial X stops being a guess.

Case 4: /kʃ/ — X before suffixes like -ious or -ual

When X is followed by a vowel-initial suffix like -ious or -ual, something similar to Case 2 happens, except it lands on /kʃ/ instead of /gz/.

Here's a pair worth noticing: anxious /ˈæŋkʃəs/ and its noun form anxiety /æŋˈzaɪəti/ — same root, but one takes /kʃ/ and the other /gz/, purely because of the suffix that follows. The letter X was never going to tell you the sound on its own — its neighbors decide.

How to actually use this

Next time an unfamiliar X word comes up, run through the checklist in order: starts the word → /z/. Followed by a consonant → /ks/. Followed by a stressed vowel → /gz/. Followed by an unstressed vowel → /ks/. Followed by -ious/-ual → /kʃ/. You don't need to memorize every word — memorize the order of checks, and most new words fall into place.

Still not sure which of the four sounds an X word takes? PHONO reads any English text through your camera and marks every word with IPA, so spelling traps like this one stop being guesswork.
Download: https://apps.apple.com/us/app/phono-english-phonetics-ipa/id6783243417 · phono.douhouse.com