to be pleased with someone or something: to accept them gladly, look on them with favor, and take delight in them
This is the heart of the word: a glad, willing approval that goes beyond merely permitting something. When God ratsah a person or a sacrifice, he does not just allow it; he welcomes it and is pleased by it. The same warmth runs the other way too, as when people are pleased with one another or take delight in a thing they want.
The word lives especially in the world of worship. A sacrifice that is ratsah is one God accepts; a sacrifice he refuses is the opposite, and the prophets use that refusal to expose worship God will not receive. Behind the offering stands the worshiper: to accept the gift is to accept the person, and to be pleased with the person is the deeper thing the offering was meant to secure.
Because the favor is glad rather than grudging, English Bibles slide between accept, be pleased with, delight in, favor, and be willing. These are shades of one idea, not separate words. The senses below sort that range: the act of receiving someone or their gift favorably, and the inward delight or willing desire that the same word also carries.