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-ible vs. -able

-ible vs. -able

-ible vs. -able

(OP)
does anyone know of a rule for using these suffixes?
Regards
Lcubed

RE: -ible vs. -able


The only one I know, which is not perfect;

if the root word is a complete word on its own, the suffix is 'able'.  e.g.  laugh+able=laughable

if the root word is incomplete, the suffix is ible e.g.vis+ible=visible

The word that screws me up every time, though is vegetable.  I keep trying to put it into that rule.

"If you are going to walk on thin ice, you might as well dance!"

RE: -ible vs. -able

vegetable doesn't have a suffix

RE: -ible vs. -able

(OP)
Yes, but if Veget were a word....

casseopeia, "usable" is one of those that doesn't quite conform, but yours is the best "rule of thumb" I've seen.  Thanks to you and to JDana.

Regards,
Lcubed

RE: -ible vs. -able


The vegetable reference was meant more as a joke because it is a frequent misspelling of mine.  I keep looking to squeeze it into a common rule so that I can remember the proper spelling, but nothing works for me.  

I think I'll start calling them vegets...I like that better than veggies.

"If you are going to walk on thin ice, you might as well dance!"

RE: -ible vs. -able

Apropos of nothing at all, Samuel Johnson defined trees as "tall vegetables" in his Dictionary.

Cheers

Greg Locock

Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.

RE: -ible vs. -able


An alternative approach from Google:

Quote:

-able vs. -ible

Susan B. Haglock wrote:

How do you know when to use -ible or -able as a suffix? The word collectible looks right to me, but collectable does not, and yet I have seen both.
The Oxford English Dictionary says it depends on whether the root word is a Latin word that ends in "ire," but I don't usually know that either.
Of all the vagaries in English spelling, this one seems to cause the most frustration and confusion, particularly when the -able/-ible form that you want can't be found in your nearby dictionary.

These suffixes are highly productive, which means that, theoretically, you ought to feel free to construct the appropriate adjective out of some verb or root plus the suffix, even when your dictionary fails to show the completed form.

Both suffixes mean 'capable of ____ing', 'susceptible of____ing', 'fit for _____ing', or 'able to be ____ed', and both are ultimately derived from Latin, -able from forms with abilis and -ible from forms with ibilis. Both suffixes also passed into English through Old French, and one comes from Latin verbs with infinitives in -are and the other from Latin verbs with infinitives in -ere or -ire. -able also forms adjectives from nouns, like pleasurable, meaning 'inclined to pleasure'.

But the fact remains that knowing all this is of very little practical help in individual cases, especially when you're ready to tear your hair and fling your dictionary to the other side of the room. Which one is it?!

As with so many things in language, there is no guaranteed solution. But there are a couple of hints with which you can try to balance the odds of getting it right.

(1): -able is often used after a full verb (although sometimes a final -e is dropped from the verb before the suffix is added): approachable, addable, teachable, photographable, acquirable. In contrast, -ible is often used after roots: credible, visible, permissible.

(2): Frequently, the -able spelling is correct when there are related derived forms with suffixes starting in -a, and the -ible spelling is similarly part of a group where other suffixes start with -i. For example, -able words may be related to words with -ance or -ation.Thus acceptable has acceptance; accusable has accusation; and applicable has application. The -ible words often have -ive or -ion related forms. Thus combustion, permissive, and audio hint at combustible, permissible, and audible.

Would that these tricks were infallible. (For example, borrowings from different forms in different languages lead to fallible but fallacy, and this would be a misleading pairing.) With some words, both suffixes have come into use (witness collectible/collectable above).

Many of you will find counterexamples for these two hints, but perhaps they can be a start.


RE: -ible vs. -able

Unnecesaary worries. There are better things to worry about in life!!!1

RE: -ible vs. -able

This is a job for ..........William F. Buckley

RE: -ible vs. -able

"The Oxford English Dictionary says it depends on whether the root word is a Latin word that ends in "ire," but I don't usually know that either."

I think that is probably true, at least I can't think of a counterexample.

The same suffixes -ible and -able exist in French, which one of the two is applicable just depends on what the associated verb ends with.

The confusion is caused by the fact that:
- English speakers pronounce "-able" and "-ible" the same way
- English verbs from Old French were transformed and some verbs systematically lost the last syllable, so it looks like "-able is often used after a full verb ... , -ible is often used after roots" but I think that is just an artefact.

As in English there are also adjectives derived from nouns in French like "presidentiable" (still some remaining election fever as you see). Not sure if there are any with "-ible" and if so why.

RE: -ible vs. -able

"-able" is still a productive suffix in English.  "-ible" for the most part isn't.  So if someone is inventing a new word ("presidentiable" is derivied from the English word "president" irrespective of its French origins), they'll use "-able".

Hg

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RE: -ible vs. -able

i always (possibly incorrectly) thought that -ible and -able depended on whether the base word had a Latin or a Greek root.  even if that is correct, it might have been useful in a bygone era of classical education, but today i think it's pretty useless !

RE: -ible vs. -able

If you take a word like divide, it is neither dividable nor dividible, but divisible.

I think I was taught some rule about the vowels - I don't remember what - but I fairly sure most i's don't get converted to a's with -able instead of -ible.

Do i's and e's generally give -ible and a's, o's and u's generally give -able?

Neglect e negligible

My one-off test just worked I think, but it could be luck!

RE: -ible vs. -able

continue u continuable
I'm too tired to think of others, goodnight!

RE: -ible vs. -able

@crystalclear

You are right but it's not the vowel in the 2nd syllable that is determining, it's the one in the 3rd syllable that disappeared when the verb transformed from Latin to English.

Use this link: http://archives.nd.edu/latgramm.htm
Take the root of the English verb to find the corresponding Latin verb, the vowel in the 3rd syllable that appears will tell you whether it's -ible or -able:
divid -> dividEre -> divisible (let's not worry about the s for now)
negl -> neglegEre -> neglegible
contin -> continuAre -> continuable

It remains a puzzle, there may be better links than this one, but this is how it works in principle.

Of course this works only with words from Latin, you won't find "laughable" in here.

@rb1957
"even if that is correct, it might have been useful in a bygone era of classical education, but today i think it's pretty useless !"
Learning Latin is probably as useful as learning to solve partial differential equations. You never seem to apply what you learned but still it makes you a smarter person...

RE: -ible vs. -able

Quote:

i always (possibly incorrectly) thought that -ible and -able depended on whether the base word had a Latin or a Greek root.

My immediate thought too.  But no end of googling backed it up.

RE: -ible vs. -able

This weekend I suddenly realised that there is more than only -ible and -able.

What about -uble: soluble!

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