New words enter the lexicon daily, but how long do any of them last?

“To adapt a biblical comparison, it seems easier for a camel to go through the eye of a needle than for a new word to take residence in the permanent vocabulary of a language,” according to Dr. Allan Metcalf (PhD), professor of English at MacMurray College in Jacksonville, Ill. and an occasional contributor to the “Lingua Franca” blog of The Chronicle of Higher Education.

“I can confidently say that the odds of a neologism becoming part of our permanent vocabulary are not nearly as long as the odds of winning half-a-billion dollars with a Powerball ticket,” Dr. Metcalf wrote in a 2012 post, in which he reviewed the factors he has identified as contributing to the longevity of new words:

• Frequency of use
• Unobtrusiveness
• Diversity of users and situations
• Generation of other forms and meanings
• Endurance of the concept

If the wording of that list seems a bit — how shall we say? “tortured”? — he said he arranged them to spell FUDGE. Before you roll your eyes, keep in mind the similarly tortured (and worse) names of some clinical trials.

The most important of the five factors, Dr. Metcalf said, is unobtrusiveness. “Consciously-coined neologisms generally are in-your-face with cleverness or humor,” he wrote. “We admire and laugh at them, but we don’t adopt them. Sometimes, though, the cleverness and humor are forgotten, and a once-funny term becomes permanent.”

Keep these FUDGE factors in mind as new words and phrases appear in posts headed “Word Watch” here.