In a manner that does not change; in a constant, permanent, or unvarying way.
From 'changeless' plus '-ly' suffix. This creates an adverb describing action or state that persists without variation.
Adverbs ending in '-lessly' are rare and often sound awkward ('hopelessly' works, but 'changelessly' feels strange), which is why you'll mostly encounter 'changelessly' in literary or philosophical writing trying to create a specific archaic or meditative tone.
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