Original: Underclothes , underclothing and underwear are formal terms , while undergarments may be more casually referred to in Australia as Reg Grundys ( rhyming slang for undies ) or Reginalds , and in the UK as smalls ( from the earlier smallclothes ) .
Simplified: In Australia , one may hear underwear being called '' Reg Grundys '' ( rhyming slang for '' undies '' ) or '' Reginalds '' , while in the UK the word '' smalls '' is sometimes used .