What's (something) in aid of?

British & Australian, informal

something that you say when you want to know why someone has done something.

I heard the shouting from the other side of the building. What was that in aid of?

A present! What's this in aid of?

• hold down something
• hold end up
• hold feet to the fire
• hold fire
• hold forth
• hold good
• hold ground
• hold hand
• hold head high
• hold head up high
• hold horses
• Hold horses!
• hold in check
• hold it
• hold its own
• hold off
• hold off something
• hold on
• hold on for dear life
• hold on like grim death
• hold onto
• hold on to for dear life
• hold on to someone for dear life
• hold onto something
• be as deaf as a post