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Webster 1913 Edition
Pillion
Pil′lion
,Noun.
1.
A panel or cushion saddle; the under pad or cushion of saddle; esp., a pad or cushion put on behind a man’s saddle, on which a woman may ride.
His [a soldier's] shank
pillion
without stirrups. Spenser.
Webster 1828 Edition
Pillion
PILLION
,Noun.
1.
A cushion for a woman to ride on behind a person on horseback.2.
A pad; a pannel; a low saddle.3.
The pad of a saddle that rests on the horse's back.