"a large medal," also applied to anything shaped like one, 1650s, from French médaillon (17c.), from Italian medaglione "large medal," augmentative of medaglia (see medal (n.)).
Entries linking to medallion
medal n.
1580s, "a metal disk bearing a figure or inscription," from French médaille (15c.), from Italian medaglia "a medal," according to OED from Vulgar Latin *metallea (moneta) "metal (coin)," from Latin metallum (see metal). The other theory [Klein, Barnhart, Watkins] is that medaglia originally meant "coin worth half a denarius," and is from Vulgar Latin *medalia, from Late Latin medialia "little halves," neuter plural of medialis "of the middle" (from PIE root *medhyo- "middle").
Originally in reference to a trinket or charm; by 1610s as a commemorative of a person, institution, or event. As a reward for merit, proficiency, etc., it is attested by 1751. A medal is distinguished from a coin by not being intended to serve as a medium of exchange, but in 18c. English, as in older French and Italian, it was applied to old coins no longer in circulation kept as curiosities. Related: Medallic.