'Geminates': Twin Sounds

Did you ever notice that some consonants are pronounced twice when they are doubled in a word’s spelling? The sounds are repeated back-to-back in quick succession, maybe sounding more like a slight pause than two separate articulations of the same letter, but try it: midday, roommate, evenness, unknown, illegal.

These doubled sounds are called geminates. Gemini is the Latin word meaning “twins,” and the astrological sign called Gemini is often represented by an image of twins or twin letters: II

This may come as a surprise if you assumed that doubled consonants made a single sound—there are plenty of examples in English, from lesson and better to classical and gallop. These words have a single consonant sound that separates the first syllable from the second.

One of the subtle and possibly annoying differences in spelling conventions between British and American English is the doubling of some consonants when verbs are conjugated, as seen in words like cancelled (British) and canceled (American). These are spelling variants that do not affect the way that we pronounce such words. They also may support the idea that the doubling of consonants (for words like support) has no effect on the way that we pronounce them.

But this isn’t quite true. A doubled consonant does sometimes indicate a different sound compared with a single letter, such as the /z/ sound made by the letter s in words like rise or advertise; think of the difference between his and hiss.

Doubled consonants also sometimes govern how the vowel is pronounced, like holy and holly, or tiny and tinny. English is tricky.

Then there are the doubled sounds that are spelled with doubled letters. When doubled letters actually represent two different word parts (linguists call them morphemes) rather than governing the phonetic qualities of the vowels or consonants themselves, we actually pronounce the doubled letter twice. These are audible if you listen for them. Think of some of the basic parts that are added to words, like prefixes and suffixes such as un- or -less or -ness. The beginning of unnecessary has two distinct /n/ sounds; if you only pronounce one of them, the word would come out sounding like “a necessary” since the initial vowel sound is the famous unstressed schwa sound, unhelpfully spelled with both u and a.

So, meanness, plainness, and thinness have two /n/ sounds. Soulless and tailless have two /L/ sounds. Filmmaker and embalmment have two /m/ sounds. If you look at the phonetic transcriptions in the dictionary, you will see both sounds expressed; for unnecessary it looks like this: ˌən-ˈne-sə-ˌser-ē. (The primary stress is given with a high mark (‘) and the secondary stress is given with a low mark (,).)

We put variable stress on syllables in English, and there’s a difference between an unstressed syllable and one that is stressed. Compare the way the second syllables are stressed in roomy and roommate and you can hear the difference. If we added stress to the second syllable of roomy it would sound like /roo-ME/, and might not even be understood as the same word.

Some of these sounds are heard as a slightly longer version of the consonant, or as a tiny pause rather than two separate sounds, as we hear in midday.

Sometimes these doubled consonant sounds occur when the two letters aren’t immediately adjacent, such as homemaker, oneness, or the common compound orange juice, which would come out like /OR-un-juice/ if we didn’t repeat the /j/ sound.

This idea of twinship was transferred to sound by linguists, who call the repetition of a consonant sound in a word a geminate sound. Keep this in mind as you go around employing the often illogical phonetic rules of English. After all, without them, you might just misspeak. Or misspell.