性能
せいのう · seinou · JLPT N2 · noun
capability
性 (nature) + 能 (ability) = built-in ability, the capability a thing has by its nature
性 means nature or property and 能 means ability. Together they name a thing's inherent capability, and in Japanese it is often used for machines: 性能 = performance.
性 — heart radical 忄 + 生 (life/birth)
性 is a semantic-phonetic compound. The heart radical 忄 supplies the meaning, pointing to inner feelings or innate qualities, while 生 ('birth, life') gives the sound and hints at what one is born with. It originally meant 'inborn nature' and later extended to 'character,' 'gender,' and 'sex.'
能 — 厶 (head) + 月 (body/flesh) + 匕匕 (legs)
Originally a pictograph of a bear, showing its head, body, and powerful legs. Because bears were seen as strong and capable, the character was borrowed to mean 'ability' or 'can'. A new character 熊 (with the fire radical 灬) was later created for 'bear'.