Incorrect spelling, explanation: a popular mistake in English is to spell the word eligible as eligable. It is true that -able is a common ending of many English adjectives and a lot of English users think that it also applies to this particular word. However, the only correct spelling is eligible.

Correct spelling, explanation: the origin of the word eligible is the Latin word eligere, which used to mean to choose. Later, also in Latin, there was the word eligibilis, which was similar to the contemporary word. Finally, however, the form eligible entered Middle English directly from French.

Definition of eligible:
1. adjective – something that meets the requirements or demands; an attractive candidate for marriage
If you’re under 18, you are not eligible to enter the club.
How could you reject the proposal of such an eligible bachelor – you will regret it.

Collocations with eligible:
Some common collocations include: eligible employees, eligible citizens, eligible to do something;
Eligible employees will get the right annual bonus.
As eligible citizens, you should go and vote for the best possible candidate.
You will be eligible to get promoted two years after we hired you.