良
リョウ, よ.い, よ.い, い.い, い.い, じ, なが, まこと, よし, ら, りょ, ろう

good, pleasing, skilled

JLPT3 G4 S7 F501

The relevant oracle bone form of this character shows a grain/kernel being washed in the flow of a pure stream → *good* (← pure) → *superior*; *truly*; *considerably*.

[Full Kanji Etymology List]