Duff (duf), n. [From OE. dagh. √67. See Dough.]
1.
Dough or paste. [Prov. Eng.] Halliwell.
2.
A stiff flour pudding, boiled in a bag; -- a term used especially by seamen; as, plum duff.
© Webster 1913
Duff (?), v. t. [imp. & p. p. Duffed; p. pr. & vb. n. Duffing.] [Etym. uncertain.] [Colloq. or Slang]
1.
To treat or manipulate so as to give a specious appearance to; to fake; hence, to cheat.
2.
In Australia, to alter the brands on (cattle, horses, etc.); to steal (cattle, etc.), and alter their brands.
© Webster 1913