ruinous

the word 'ruinous' is built upon the core concept of 'ruin', which originates from the latin verb 'ruere', meaning to fall violently or collapse. the latin noun 'ruina' specifically denoted the result of such a collapse, a physical downfall or destruction. the suffix '-ous', of latin origin, is added to nouns to form adjectives meaning 'full of' or 'characterized by'. therefore, 'ruinous' literally means 'full of ruin' or 'characterized by destruction', a meaning that has remained consistent from its formation into modern english, describing either something that causes complete disaster or something that is in a state of decay.

Structure: ruin (noun/verb) + ous (adjective suffix) ruin (from latin ruina 'a collapse, a falling down', from ruere 'to fall violently, rush down'); ous (from latin -osus, a suffix forming adjectives meaning 'full of, characterized by').