Riley, Murdoch, "Maori Sayings and Proverbs", Paraparaumu: Viking Sevenseas,
1990

" 'He kupu matangerengere' 'A harsh word.' A word having a 'hideously ulcerated
face.' A saying applied to a word, to a sentence or to a speech."

It seemed appropriate to the discourtesy being expressed in one or more
previous emails on the subject being discussed.