Causing or involving loss, damage, or harm; injurious or harmful in nature.
From Latin damnosus, derived from damnum (loss, damage). This is an archaic or obsolete English adjective that parallels the more common harmful or injurious.
This adjective is essentially a dead word in English — 'damnous' never caught on the way other Latin-derived adjectives did, probably because 'harmful' and 'damaging' worked just fine and sounded less religious.
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