Abarim Publications' online Biblical Hebrew Dictionary
יכל
The common verb יכל (yakol) means to "can"; that is: to be able, to prevail or to overcome. Besides the usages that are parallel to the English verbs can and be able to, this verb also appears in the meaning of to prevail or overcome. It's used in this way in the enigmatic scene in which Jacob wrestles the Man at the Jabbok (Genesis 32:25) and also in Goliath's taunt that would produce David ("If I prevail against him . . . " - 1 Samuel 17:9).
Apparently, the Hebrew idea of a skill was grafted on the idea of mastery rather than ability. But whether a skillful person was reckoned to have mastered a challenge or rather his competitors isn't clear.
This verb has no derivatives. Also see the word חכמה (hokma), meaning wisdom.