Double consonant: when should I use them?


I would like to know a clear rule about when should I use double consonant.

For example: intelligent (yes), little (yes), collapse (yes), elegant (no).

Not just about double l, but in general, is there any rule for double consonants?


Posted 2016-06-09T02:47:38.917

Reputation: 229

Unfortunately, there is no clear answer. However, I wrote an answer to a similar question on ELU that I hope will be somewhat helpful: Rules for spelling double consonants in roots of words Etymologically, intelligent has the prefix inter- which assimilates to intel- before the consonant l.

– sumelic – 2016-07-28T21:18:27.977



There are some languages that have very clear, consistent rules about how words are spelled, and how that spelling translates into pronunciation. Unfortunately, English is not one of those languages.

English started as a Germanic language, but was then heavily influenced by French (and thus Latin), apparently due to the Norman Conquests. Since then, a variety of other languages have had varying degrees of influence on English. Thus, English is a mixture of many different standards, making it inconsistent.


Posted 2016-06-09T02:47:38.917

Reputation: 572


That's vocabulary. There are no rules for that.

When you double consonants, it applies in general for -ing forms, comparative & superlative adjectives & past simple with regular verb forms.

It's like asking: why travelling and not traveling? Because BrE use the former and AmE the latter. It's just vocabulary.


Posted 2016-06-09T02:47:38.917

Reputation: 3 795

I never thought about the BRE and AME situations (thanks), how each one deals with the double consonant.. but for example.. you mean.. it's ok to use "perfectly" and "perfectlly"? – ivanleoncz – 2016-06-09T03:08:28.283

That's different: perfectly is correct, the one with double l not. Sometimes, when constructing adverbs, you get to have a doble l. For instance, careful - carefully** – Alejandro – 2016-06-09T03:12:11.153

1I can't think of an example where double L would be added to a word that originally had no L's. – nnnnnn – 2016-06-09T03:53:20.337

1The AmE rule is if the emphasis is on the last syllable, you double the consonant: rappel => rappelling vs travel => traveling. Also, for single syllable words ending in a consonant, you would double: put => putting, let => letting. – MrWonderful – 2016-06-09T07:09:47.260

@MrWonderful Makes much more sense now (thanks). Is it possible to have special cases like "intelligent"? – ivanleoncz – 2016-06-09T13:59:14.700