共性
gòng xìng · HSK 7
overall character
共 (shared/together) + 性 (nature/character) = shared nature
共 means together or in common; 性 means nature or character. Together they name the traits a group of things all share — their common nature, or overall character.
共 — 两手 (廾) holding up an object
共 originally depicted two hands raised together, lifting or offering something jointly. The ancient form showed a vessel or object held up by paired hands, conveying shared action. From 'lifting together' it shifted to mean 'together,' 'common,' or 'share.'
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.'