学 is one of the most commonly used Japanese kanji, and it also has a lot of special readings in addition to the standard onyomi and kunyomi readings.
ONYOMI 音読み
まな.ぶ mana.bu
KUNYOMI 訓読み
ガク gaku
Examples
何人も学があるということでいっそう賢いということはない。No man is the wiser for his learning.彼は非常に学がある。He is very learned.少年老い易く学成り難し。Art is long, time is fleeting.学のある人はとかく無知な人を軽蔑する。The learned are apt to despise the ignorant.