Suffusion

"The device [electronic I Ching calculator] also functioned as an ordinary calculator, but only to a limited degree. It could handle any calculation which returned an answer of anything up to 4. ...anything above 4 it represented merely as 'A Suffusion of Yellow.' Dirk was not certain if this was a programming error or an insight beyond his ability to fathom, but he was crazy about it anyway, enough to hand over twenty pounds of ready cash for the thing."
--Douglas Adams
"The Long Dark Tea-Time of the Soul" (1988)