In a Word: The Guilt in Innocence

Senior managing editor and logophile Andy Hollandbeck reveals the sometimes surprising roots of common English words and phrases. Remember: Etymology tells us where a word comes from, but not what it means today. 

In Latin, the verb nocere means “to harm, to hurt.” One of its derivative forms is noxa “harmful,” and the nox- part of that word survives in English today. No, it isn’t the one at the end of equinox; it’s the one in noxious (“harmful to living beings”) and obnoxious — the ob- prefix means “toward.” 

A couple of other words have found their way to English from nocere too, but their familial link to noxious and obnoxious isn’t quite so obvious. Nocuus is another form that means “harmful,” and nocentem is something closer to “harming,” though later it meant “guilty.” 

Latin isn’t all about harm and guilt, but it seems sometimes that the language can focus on that. It’s an aspect of many European languages that, rather than having a separate word that means “harmless” or “not guilty,” an affix is added to the word for “harm, guilt” to indicate its opposite. And that’s what happened in Latin. There are a few such negating prefixes available, but in this case it was in-, meaning “not.”  

So, nocentem gave rise to innocentem, which became the Old French inocent. In the 14th century, English had adopted it as innocent, originally in a sense of “harmless, free from sin” (as in “innocent children”), but by the end of that century it had been taken up as a legal term, “not guilty of a particular accusation.” 

Meanwhile nocuus got the same prefix, creating innocuus, which around the end of the 16th century had become the English innocuous, “harmless, producing no ill effect.”  

Etymologically, innocent and innocuous are practically the same word, which is a fact I personally use as a mnemonic device. Remembering the number of ns in innocuous can be trick, especially if you sometimes confuse it with the word inoculate. However, I for one can remember the double-n in innocent, so if I remember that innocent and innocuous are closely related, I can remember to double the n in the latter. (Then I only have to worry about how many ns are in inoculate.)