1) Agent 2) Bid hearer 3) Bid solicitor 4) Bidding salesman 5) Block head 6) Broker 7) Factor 8) Grown man who cries 9) Hammer wielder 10) One who sees to your bidding 11) Professional talker 12) Salesman of a sort 13) Sell at an auction 14) Seller of lots 15) Seller with a gavel 16) Special kind of salesman 1) Seller 
• (v. t.) To sell by auction; to auction. • (n.) A person who sells by auction; a person whose business it is to dispose of goods or lands by public sale to the highest or best bidder.
The person who conducts an auction. The auctioneer introduces each lot offered for sale, acknowledges bids, and announces whether lots are sold or unsold and their final bid prices.
Auc`tion·eer' noun A person who sells by auction; a person whose business it is to dispose of goods or lands by public sale to the highest or best bidder. 
[n] - an agent who conducts an auction
noun an agent who conducts an auction
a person who conducts sales by auction.