From Wikipedia:
'RIS?' – 'I do not understand' – this phrase originates from an image of a Morrisons sign posted by ThatFineLine, where the letters RIS had been extinguished, leaving the word MORONS. [4] See also: LWORTHS (Curis) and DAE (Lord Manley).
(
shrinking man Been away a while, time I ventured back,
Wed 26 Sep 2007, 16:18,
archived)