Real Dictionary

-able
suffix: -able combines with verbs to form adjectives. Adjectives formed in this way describe someone or something that can have a particular thing done to them. For example, if something is avoidable, it can be avoided.

-able in American English
that can or will
suffix: a suffix meaning “capable of, susceptible of, fit for, tending to, given to,” associated in meaning with the word able, occurring in loanwords from Latin (laudable); used in English as a highly productive suffix to form adjectives by addition to stems of

-able in British English
suffix forming adjectives: capable of, suitable for, or deserving of (being acted upon as indicated)

able
adjective: Someone who is able is very clever or very good at doing something.

able in American English
having enough power, skill, etc. to do something
adjective: having necessary power, skill, resources, or qualifications; qualified
noun: a code word formerly used in communications to represent the letter A

able in British English
adjective: having the necessary power, resources, skill, time, opportunity, etc, to do something