- willow (n.)
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- Old English welig "willow," from Proto-Germanic *wel- (source also of Old Saxon wilgia, Middle Dutch wilghe, Dutch wilg), probably from PIE *wel- (3) "to turn, roll," with derivatives referring to curved, enclosing objects, cognate with Greek helix (see volvox). The change in form to -ow (14c.) paralleled that of bellow and fellow. The more typical Germanic word for the tree is represented by withy.