To worry, fret, or be anxious; to burden or oppress with cares and anxieties.
From Old Norse 'kerkja' (to turn, bend, distress) or possibly related to Old English 'cearu' (care, sorrow). The verb developed its meaning of causing anxiety or burden through association with the weight of cares.
The word 'cark' is still alive in Australian English where 'cark it' means to die or fail dramatically—it's a perfect example of how British English words survive longer in former colonies while fading at home!
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