verb
aids; aided; aiding
to provide what is useful or necessary :help [+ obj]
usually + in
noun
plural aids
[noncount] :the act of helping someone :help or assistance given to someone
[noncount] something (such as money, food, or equipment) that is given by a government or an organization to help the people in a country or area where many people are suffering because of poverty, disease, etc.
money that is given to a student to help pay for the cost of attending a school
[count] something that provides help or assistance
a device, object, etc., that makes something easier to do
[count] chiefly US :a person whose job is to assist someone :aide
in aid of
chiefly Brit :in order to help (something or someone)
The informal British expression What's (all) this/that in aid of? is used to ask about the purpose of something.