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A tacksman (Scottish Gaelic: Fear-Taic, meaning "supporting man") was a land-holder of intermediate legal and social status in Scottish Highland society.
Although a tacksman generally paid a yearly rent for the land let to him (his "tack"), his tenure might last for several generations. He would often be related to his landlord, the free-holder, and might, for example, represent a cadet branch of the family of the clan chief. The tacksman in turn would let out his land to sub-tenants, but he might keep some in hand himself. Dr Johnson defined the class in this manner:
"Next in dignity to the laird is the Tacksman; a large taker or lease-holder of land, of which he keeps part as a domain in his own hand, and lets part to under-tenants. The tacksman is necessarily a man capable of securing to the laird the whole rent, and is commonly a collateral relation. These tacks, or subordinate possessions, were long considered as hereditary, and the occupant was distinguished by the name of the place at which he resided. He held a middle station, by which the highest and the lowest orders were connected. He paid rent and reverence to the laird, and received them from the tenants. This tenure still subsists, with its original operation, but not with its primitive stability".[1]
The three fundamental obligations traditionally imposed on tacksmen were grassum (a premium payable on entering into a lease), rental (either in kind, or in money, which was designated "tack-duty"), and the rendering of military service.[2]