Definify.com
Webster 1913 Edition
Valentine
Val′en-tine
,Noun.
1.
A sweetheart chosen on St. Valentine’s Day.
2.
A letter containing professions of love, or a missive of a sentimental, comic, or burlesque character, sent on St. Valentine's Day.
St. Valentine's Day
, a day sacred to St. Valentine; the 14th of February. It was a very old notion, alluded to by Shakespeare, that on this day birds begin to mate. Hence, perhaps, arose the custom of sending love tokens at that time.
Webster 1828 Edition
Valentine
VAL'ENTINE
, n.1.
A sweetheart or choice made on Valentine's day.2.
A letter sent by one young person to another on Valentine's day.