Hereditary in gross

Under feudalism in England during the mediaeval era, tenure by serjeanty was a form of tenure in return for some specified non-standard service, thus distinguishing it from knight-service. It is also used of similar forms in Continental Europe.

The word comes from the French noun sergent, itself from the Latin serviens, servientis, "serving", the present participle of the verb servo, "to keep, preserve, save, rescue, deliver".

Serjeanty originated in the assignation of an estate in land on condition of the performance of a certain duty other than knight-service, usually the discharge of duties in the household of the king or a noble. It ranged from non-standard service in the king's army (distinguished only by equipment from that of the knight), to petty renders (for example the rendering of a quantity of basic food such as a goose) scarcely distinguishable from those of the rent-paying tenant or socager.

The legal historians Pollock and Maitland (1895) described it as being a free "servantship" in the sense that the serjeant, whatever his task, was essentially a menial servant. However the feudal historian Round objected that their definition does not cover military serjeanties and glosses over the honorific value of at least some of the services.

The historian Mary Bateson stated as follows concerning serjeanties:

(They) were neither always military nor always agricultural, but might approach very closely the service of knights or the service of farmers ... The serjeanty of holding the king's head when he made a rough passage across the Channel, of pulling a rope when his vessel landed, of counting his chessmen on Christmas day, of bringing fuel to his castle, of doing his carpentry, of finding his pot-herbs, of forging his irons for his ploughs, of tending his garden, of nursing the hounds gored and injured in the hunt, of serving as veterinary to his sick falcons, such and many others might be the ceremonial or menial services due from a given serjeanty.

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