イタリア語で monta in banco, charlatan, juggler から。 monta, ride, straddle が語源で、mount, banco, bench と語源は同じ。 縁日でベンチを設置して犬の品物を売る人を風刺するのに使われる。
英語の語源
mountebank (n.)
"a doctor that mounts a bench in the market, and boasts his infallible remedies and cures" [Johnson], 1570s, from Italian montambanco, contraction of monta in banco "quack, juggler," literally "mount on bench" (to be seen by crowd), from monta, imperative of montare "to mount" (see mount (v.)) + banco, variant of banca "bench" (see bank (n.2)). Figurative and extended senses from 1580s.