I read this Merriam-Webster article about the difference between “iced tea” and “ice tea” in written and spoken form. I liked the article, but I can explain in more detail why they sound the same.

In written form, “iced tea” is more common in the US and “ice tea” more common in the UK.

When spoken, you won’t hear a difference. Why?

A: We don’t speak in individual sounds. We speak in syllables.

Video of me demonstrating

Spoken form and written form are very different.

What you see isn’t always what you hear.

What you hear isn’t always what you see.

You understand words as units of meaning but when spoken, there aren’t pauses every place there is white space between words when written. When you listen to someone speak a language you don’t know, can you tell where the individual word boundaries are? It can sound like a long string of continuous sounds that have no meaning to you.

If you make it to the end of this article, you’ll understand why:

Looks like, “ice tea.” Sounds like, “ais tee.” The IPA transcription: /'ɑ͜ɪsti/

Looks like, “iced tea.” Sounds like, “ais tee.” The IPA transcription: /'ɑ͜ɪsti/

What’s Happening: “Coarticulation”

The word “coarticulation” comes from Latin:

co-  - at the same time, together

articulus, artus - separate into joints, utter distinctly

-ion - condition of, makes a noun from a verb

This means the separate “joints” of sound are being produced in coordination with each other, not so separated. All sounds are affected by the sounds around them as your tongue and muscles make the movements from one sound to another, whether they are in one word or across multiple words. This creates sounds that may not be seen in the written form or leave out sounds that are in the written form. 

Example - The first sound is affected by the second sound.

“she” - The lips are not rounded for the “sh” because the “e” /i/ vowel requires the lips to be unrounded.

“shoe” - The lips are rounded for the “sh” because the “oe” /u/ vowel requires the lips to be rounded.

When a “d” is a “t”

The “-ed” ending in “iced” doesn’t sound like a /d/ at all. It actually sounds like a /t/.

The “-ed” suffix sounds like /t/ when the final sound in the word it is being added to is voiceless, meaning the vocal folds are not touching and creating sound. So it may look like “iced” but it really sounds like “icet.” Since the “c” really sounds like /s/, we could spell it the way it sounds, “aist.”

Places Everyone!

These sounds are all made by placing the tip of the tongue on the roof of the mouth just behind your top front teeth (that place is the “alveolar ridge”): /t, d, n, l/ and these get close but don’t touch the top of the mouth: /s, z, r/.

The /t/ and /d/ sounds stop the airflow completely by blocking the air from leaving the mouth, pressure builds up behind the tongue, and you release the tongue with a burst of air (this is why they are called “stop” and “plosive” sounds).

The rest of the sounds don’t stop the airflow: /n, l, s, z, r/. They obstruct it in some way, but the air continues flowing out of the mouth.

Stop & Go

The final /t/ (or any stop consonant: /p, b, t, d, k, g/) doesn’t need to be heard. Your tongue moves to the /t/ position and holds the airflow from leaving your mouth.

Say the word “great” and don’t release the airflow of the /t/. You won’t hear the /t/.

When there is a vowel after a stop consonant, you move your tongue down to release the airflow and the consonant is heard.

Say the words “hold on” and as you release the airflow for the /d/ you’ll hear the /d/ sound as you begin to pronounce the vowel in “on.”

When there are two stop consonants next to each other, the first one is held and not heard, then the second one releases the airflow and is heard.

“good day” - The tongue holds the final /d/ in “good” then the airflow is released for the /d/ in “day.” You only hear one /d/. This avoids an extra sound from being heard between them which happens when you try to speak too clearly, “good-uh-day.”

“big deal” - Same situation, different sounds. Stop and hold air on the /g/ and release air and hear the /d/.

“iced tea” - Same situation, different sounds.

The tongue goes to the /t/ position for end of “iced” and holds the airflow from leaving the mouth until the tongue moves down and releases the airflow for the /t/ in “tea.” You only hear one /t/, not “aist-uh-tea.”

“ice tea” - The final sound in “ice” isn’t a stop consonant. The air keeps moving as you make the /s/ sound. Then your tongue tip presses up against the roof of the mouth and stops the airflow to get ready to make the /t/. When the tongue lowers and the airflow is released, you can hear the /t/ sound.

Both “iced tea” and “ice tea” stop the airflow and then release it. The first /t/ which looks like “ed” is never heard.

That’s why:

Looks like, “ice tea.” Sounds like, “ais tee.” The IPA transcription: /'ɑ͜ɪsti/

Looks like, “iced tea.” Sounds like, “ais tee.” The IPA transcription: /'ɑ͜ɪsti/

And now that I see how long this is, that’s probably why the Merriam-Webster article didn’t get into all the details.