A restraint, cuff, or bracelet worn around the hand or wrist, either for practical or ceremonial purposes.
Compound of 'handy' (relating to the hand) and 'cuff' (from Middle Dutch 'coffe'), though 'handcuff' is the standard spelling.
We use 'handcuff' (not 'handycuff'), but this variant shows how -y was once used to form adjectives meaning 'pertaining to'—like 'mossy' (full of moss) or 'bloody' (full of blood), so 'handycuff' would mean 'of or relating to hands.'
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