In a manner that is bleak, cold, and without comfort or consolation; in a desolate or unwelcoming way.
From 'comfortless' (comfort + -less, from Old English 'lēas': without) + '-ly' adverb suffix. Stacks two suffixes on a Latin root.
The phrase 'comfortlessly' is rarely used because people prefer saying 'without comfort' or 'bleakly'—it shows how adding multiple suffixes (comfort-less-ly) sometimes creates words that sound clunky compared to alternatives.
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