a bridge partner who increases the partner's bid
"After my partner opened the bidding, I felt confident enough to step in as the raiser and double our stake by raising their contract."
someone concerned with the science or art or business of cultivating the soil
"The local agricultural society hired a new raiser to teach farmers better techniques for growing wheat in our dry climate."
A person or thing that raises.
"The new community center acts as a fundraiser for local charities, but it also serves as a great place to meet neighbors who are interested in becoming volunteers and raisers of funds themselves."