from
Bouvier's Law Dictionary, Revised 6th Ed (1856)
AIDS, Engl. law. Formerly they were certain sums of money granted by the
tenant to his lord in times of difficulty and distress, but, as usual in
such cases, what was received as a gratuity by the rich and powerful from
the weak and poor, was soon claimed as a matter of right; and aids became a
species of tax to be paid by the tenant to his lord, in these cases: 1. To
ransom the lord's person, when taken prisoner; 2. To make the lord's eldest
son a knight; 3. To marry the lord's eldest daughter, by giving her a
suitable portion. The first of these remained uncertain; the other two were
fixed by act of parliament at twenty shillings each being the supposed
twentieth part of a knight's fee, 2 Bl. Com. 64.