solidarity

The word "solidarity" entered English in the mid-19th century from the French solidarité, which itself was a legal term derived from the Latin solidum (a whole sum). The core Latin root is solidus, meaning firm, dense, or whole. The conceptual journey is from the physical property of being a solid, unbroken mass to the abstract social principle of unity and mutual support that makes a group firm and cohesive. Thus, the logic of the word links the physical integrity of a solid object to the moral and social integrity of a united community.

Structure: solid (firm, whole) + arity (noun suffix denoting state or condition) - solid: From Latin solidus (firm, whole, dense). In this word, it conveys the sense of a firm, unified whole. - arity: A noun-forming suffix derived from Latin -arius (pertaining to) via French -arité, indicating a state or condition.