What is Grand?

Legal Definition
An epithet frequently used to denote that the thing. to which it is joined is of more importance and dignity, than other things of the same name; as, grand assize, a writ in a real action to determine the right of property in land; grand cape, a writ used in England, on a plea of land, when the tenant makes default in appearance at the day given for the king to take the land into his hands; grand days, among the English lawyers, are those days in term which are solemnly kept in the inns of court and chancery, namely, Candlemas day, in Hilary term; Ascension day, in Easter term; and All Saint's day, in Michaelmas term; which days are dies non juridici. Grand distress is the name of a writ so called because of its extent, namely, to all. the goods and chattels of the party distrained within the county; this writ is believed to be peculiar to England. Grand Jury. (q. v.) Grand serjeantry, the name of an ancient English military tenure.
-- Bouviers Law Dictionary
Legal Definition
As to grand "Assize," "Bill of Sale," "Cape," "Distress," "Jury," "Larceny," and "Serjeanty," see those titles.
-- Black's Law Dictionary