IPA: //ˈɔːrdərər//
KK: /ˈɔrdərər/
A person who requests or arranges for something to be delivered or provided.
The orderer placed a large order for supplies.
Orderer → It is formed from "order" (from Old French *orde*, meaning arrangement or sequence) and "-er" (meaning a person who). An orderer is a person who arranges or organizes something.
Think of someone who is responsible for 'arranging' ('order') things — that's what an orderer does.