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-able and -ible
2

-able and -ible

-able and -ible

(OP)
From another thread, it was asked if there are any rules with respect to using -able and -ible.  I thought perhaps this might be worth its own thread.

As a general rule, apply the following:

If the root can stand on its own, then use able.  If the root cannot stand alone, then use ible.  

suitable - suit can stand on its own.
drinkable - drink can stand on its own.
terrible - terr cannot stand on its own.
horrible - horr cannot stand on its own.

Another way to do a quick check, is to ask if the root is "able".  Are you able to terr?  Are you able to drink?

Using a dictionary is of course best because there are exceptions (flexible, inevitable), but more often than not, this rule will be right.

RE: -able and -ible

terror
horror

RE: -able and -ible

(OP)
Using those roots, your words would be:

terrorable?  horrorible?
terrorible?  horrorible?  

RE: -able and -ible

Just examining the roots, that's all.  The "stands on its own" rule doesn't quite seem applicable.

Perhaps it's a noun vs. verb thing?  Terror, horror, response--nouns.  Suit, drink--verbs (in this case).

Due to illness, the part of The Tick will be played by... The Tick.
http://www.EsoxRepublic.com

RE: -able and -ible

(OP)
Yes, the general rule is just examining the root, that being the portion of the word prior to the prefix.  Terror and horror are not the roots.  Terr and Horr are the roots for the purposes of this general rule.

I also said, and underlined for emphasis, that there are exceptions.

Applicable is an exception, but an understandable one since it ultimately comes from the Latin applicare.

Responsible is also an exception, and as far as I know, one that you just have to memorize.

You point about nouns and verbs is a good one, and there are certainly parallels, but I'm not sure if it's better or worse, with respect to the number of exceptions, as the general rule.  It may very well be.  For those words that are both nouns and verbs (digest - digestible), you'll always be right, just call it a noun or verb whichever you need.

RE: -able and -ible

Thanks CajunCenturion

This is something that I wasn't aware of and it will be of great help in the future. I always had to look up those types words in the dictionary. Even though, as TheTick points out it may not always apply it certainly gives me a starting point. Most rules don't apply in all circumstances.

Although the words Tick chose as an example stand out visually as being mis-spelled, when -ible or -able are added --- maybe it's just me.


Thanks again for the guidelines

ietech

RE: -able and -ible

It is not my intention to undermine the validity of the rule.  I was just exploring whether the rule was a cause or an effect--does the rule beget the spelling or does the spelling beget the rule.

Thanks for posting it, CajunCenturion.

Due to illness, the part of The Tick will be played by... The Tick.
http://www.EsoxRepublic.com

RE: -able and -ible

TheTick

Thanks also for the point about nouns and verbs. I will add this to my thoughts when spelling this type of word.

ietech

RE: -able and -ible

(OP)
The noun/verb issue has prompted me to do some digging and here is summary of what I found.

There is a correllation in that most verbs which came from French take the able ending.  Other words, both nouns and verbs, which find their roots in Latin tend to use ible.

I also came across another gem to add to the general rule.  Words that end in the "s" or "z" sound usually take ible.

Responsible, sensible, accessible, possible are such examples.

With respect to spelling.  If the root ends in the letter "e", then you drop the "e", then add the able/ible suffix.

RE: -able and -ible

To CajunCenturion, would you then classify the following: manageable, traceable, serviceable and sizeable, as exceptions to the rule ?

RE: -able and -ible

Those fit the original rule.  What's the joke?

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RE: -able and -ible

The definition in my copy of Fowler's is that in general:

"-able" is an active suffix that can be freely added to the stems of transitive verbs, whereas the set of "-ible" words is a closed set with meanings that are less susceptible to analysis.

I think this is more or less paraphrasing what CajunCenturion first said. i.e. if you are able to "perform" the stem action, chances are the root is a transitive verb, and the rule therefore applies.

E.g. "excuse" is a transitive verb; hence "excusable".

"neglig" is not a transitive verb (as far as I can work out!), hence "negligible".

However, as for just about every rule in English, there are just about as many exceptions as there are adherents to the rule!

E.g. "convert" is a transitive verb, so the rule would suggest "convertable", but it is in fact "convertible".

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