also: ダファー
noun
duffer
Loanword from English 'duffer', referring to an incompetent or useless person, or in golf, a poor player. Usage is niche and may not be widely understood outside specific contexts.
ゴルフ仲間は彼のことを「ダッファー」と呼んでいる。
His golf buddies call him a 'duffer'.