A young or small creature that is weak or frail, or the act of becoming feeble.
From 'feeble' with the diminutive and agent suffix '-ling,' which originally denoted something small or inferior (as in 'duckling'), though this usage is now archaic or dialectal.
The '-ling' suffix was incredibly productive in Old English for creating diminutives—'feebling' means something like 'a weak little thing'—and we still see it in modern words like 'duckling,' 'sibling,' and 'hireling,' all carrying echoes of something small or subordinate.
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