Definitions of able:

• adjective:   (usually followed by `to') having the necessary means or skill or know-how or authority to do something

  Example: "Able to swim"

• adjective:   having inherent physical or mental ability or capacity

  Example: "Able to learn"

• adjective:   have the skills and qualifications to do things well

  Example: "Able teachers"

• adjective:   having a strong healthy body

  Example: "An able seaman"

• name:  A surname (rare: 1 in 100000 families; popularity rank in the U.S.: #12109)