volatile [ME] This was first used as a noun meaning a ‘creature that flies’, and it was also a collective word for ‘birds’. It derives from Old French volatil from Latin volare ‘to fly’. The association of the word with temperament is found from the mid 17th century, and with liquids that evaporate quickly by the later 17th. The flying shot called a volley [L16th] comes from the same source.