"The cowboy was a board-whacker. Each time that he held superior cards he whanged them, one by one, with exceeding force, down upon the improvised table, and took the tricks with a glowing air of prowess and pride that sent thrills of indignation into the hearts of his opponents. A game with a board-whacker in it is sure to become intense. The countenances of the Easterner and the Swede were miserable whenever the cowboy thundered down his aces and kings, while Johnnie, his eyes gleaming with joy, chuckled and chuckled." (The Blue Hotel by Stephen Crane) http://www.4literature.net/Stephen_Crane/Blue_Hotel/2.html
Please tell me what a "board-whacker" means in the paragraph. (these men, including the cowboy, was playing a game of high-five)
Thank you.
Cadzao