What is skewflation?

Skeflation refers to inflation in some commodities , deflation in others. India’s Economic survey 2010-11 says:
The year 2010-11 has been a year of more than one such skewflationary episode. At the beginning of the calendar year 2010 and even in the first months of the fiscal year 2010-11 inflation was high for food grains, sugar, and pulses. During the course of the year, inflation in these commodities stabilized, but by November there was another spike in prices of another set of commodities, led by onions, cabbage, milk, and a couple of other products.