rifler1
/ˈrʌɪflə/ /ˈrʌɪf(ə)lə/(also rifeler)
noun
A robber, a plunderer, a looter.
Origin
Middle English. Probably partly (in early use) from Anglo-Norman ryflour, Middle French rifleur, riffleur robber, thief, and partly from rifle + -er. Compare post-classical Latin riflator, rifliator, riflerius (after 1341 in a British source).
rifler2
/ˈrʌɪflə/ /ˈrʌɪf(ə)lə/noun
= rifleman. Now rare.
Origin
Late 18th century. From rifle + -er. Compare earlier rifleman.