(1):
(n.) An agent between two parties; a broker; a go-between; any dealer between the producer and the consumer; in Ireland, one who takes land of the proprietors in large tracts, and then rents it out in small portions to the peasantry.
(2):
(n.) A person of intermediate rank; a commoner.
(3):
(n.) The man who occupies a central position in a file of soldiers.