An obsolete or dialect term for an ell (a unit of measurement), or possibly a variant spelling of a historical measuring standard.
Possibly from Old English 'eln' or Dutch 'alen,' related to 'ell' (an arm-length measurement); exact etymology and current usage are uncertain.
Alen is one of those measurement words that died out—like 'furlong' and 'fathom,' it's a time capsule of how people used body parts to measure before standardized metrics!
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