also: かいしょ
noun
resourcefulness; ability to get things done; dependability
Refers to a person's practical competence, especially the ability to earn a living, manage affairs, and be relied upon. Often used in contexts of marriage or family responsibility.
彼は甲斐性があるから、結婚しても安心だ。
He is resourceful and dependable, so I would feel secure marrying him.
甲斐性の
I got fed up with my husband who lacks the ability to support the family.
頼りになる simply means 'reliable' or 'dependable' in a general sense. 甲斐性 specifically implies practical resourcefulness and the ability to provide, often in a domestic or financial context.
有能 means 'competent' or 'capable' in a professional or skill-based sense. 甲斐性 is broader, encompassing life skills, reliability, and the ability to support others.
Compound of 甲斐 (kai, 'effect; worth') and 性 (shō, 'nature; quality'). The exact historical derivation is uncertain, but the word has long been used to describe a person's practical worth and reliability.