Laird might just have been a nickname here. But, alternatively, there was a class of tenants known as "Bonnet Laird's" who farmed the land at a nominal rent on a long lease or tack (99 years often).
In the Highlands a clan often owned no land at all, the chief was due rent to a feudal superior, (if he paid it at all!) and the land was parcelled out to the clan's "Tacksmen", generally the chief's relatives, who lived off the rents (often in kind) of the tenants, paid the chief his rent and pocketed the difference. Land being a finite resource, when a tack expired it was often re-granted to a nearer relative of the chief, he had to look after the welfare of his own immediate family, so cousins became disposessed.
Rents, or the non-payment of them, was the cause of much conflict. The last clan battle, Mulroy, was fought over this issue.
Skoosh.