A friend asked for the tale behind the nursery rhyme pease porridge hot, pease porridge cold, pease porridge in the pot nine days old. She knew that pease porridge is better known nowadays as "pea soup," but what she didn't know was the pea-pease connection.

The story is an old one: once upon a time, a seed of the leguminous vine was called a pease. The presence of that terminal "s" sound gave rise to the belief that pease was plural, and so, in the early 1600s, the singular pea was born and quickly took root.

Why do we describe the story as an old one? Because pea shares its "born in error" history with words ranging from pry to eave, to cherry and kudo. All those terms were created from erroneous beliefs about the plural status of their linguistic ancestors. So why don't we simply weed out the incorrect pea and replace it with the proper pease and its plural peases?

Because that's not the way English works. We don't have a regulatory board to uproot or approve words. But we did dig up one recent term, born in misunderstanding, that has come in for its share of criticism. The word is kudo, a back-formation from the Greek kudos. Some commentators believe that since kudos is singular, it cannot be used as a plural and that the word kudo is therefore impossible. But 50 years of usage suggests otherwise, and we believe kudo, like pea and its friends, is now firmly planted in the language.