Learn English – Difference in “capable” and “able”

differencesword-choice

What is the difference in being physically capable and physically able?

When would one choose one over the other?

Best Answer

One main difference is the preposition that usually follows each of these words. Typically, you see able to, but capable of.

Other than that, pick a dictionary, look the two words up. I'm citing Collins:

able (adj.)
1. having the necessary power, resources, skill, time, opportunity, etc, to do something ⇒ able to swim
2. capable; competent; talented ⇒ an able teacher
3. (law) qualified, competent, or authorized to do some specific act

capable (adj.)
1. having ability, esp in many different fields; competent
2. able or having the skill (to do something) ⇒ she is capable of hard work
3. having the temperament or inclination (to do something) ⇒ he seemed capable of murder

You can see a lot of overlap, particularly with definitions #1 & #2 for capable, and definition #2 for able. Both words mean competent; plus, able means capable, and capable means able. This means there will be several contexts where either word could be used:

Sammy is an able electrician; I would recommend him.
Tammie is a capable electrician; I would recommend her.

Evan has shown he is able to reach the green from the tee box.
Kevin has shown he is capable of reaching the green from the tee box.

However, the definitions also show instances where one word couldn't be exchanged for the other:

I have to catch a flight; I won't be able to hold the meeting this afternoon.
⇒ This is able Definition #1; capable is not appropriate here.
Because I didn't apply in time, I won't be able to start college this fall.
⇒ This is able Definition #3; capable is not appropriate here.
Melvin is a lazy student; he isn't capable of finishing college.
⇒ This is capable Definition #3; able is less appropriate here.
Dorothy doesn't know what she is doing; she isn't capable of holding the meeting today.
⇒ This is capable Definition #1; but able might be appropriate here.