This week, Lady Gaga lit up Twitter with a simple question: “What’s fortnight?”
— Lady Gaga (@ladygaga) October 15, 2019
As the viral response to her tweet made plain, Gaga had apparently confused fortnight with the massively popular online video game—and homonym—Fortnite.
Gaga’s question also lit up searches on Dictionary.com for fortnight, which, compared to data from, well, a fortnight ago, went up over 2,100%. We’ll acknowledge that this surge was probably influenced by our own hot take:
The good news is it won't take us two weeks to answer. https://t.co/EWPU13kKP2
— Dictionary.com (@Dictionarycom) October 15, 2019
Now, Mother Monster’s confusion over fortnight/Fortnite is certainly understandable. (Just ask the countless parents and partners who have no idea what it is, exactly, their loved ones are doing in the basement.)
But, lexically speaking, we think she really does ask a good question: What even is a fortnight, anyways?
What is a fortnight?
A fortnight is “a period of two weeks,” that is, “fourteen days and nights.” The number fourteen, here, is more than just another way to gloss how long two weeks is, though. It actually explains that confusing fort- in fortnight—which has nothing to do with army forts or pillow forts.
Fortnight comes from the Middle English fourtenight, which is contracted from the Old English fēowertēne niht. We suspect you don’t need to be a time-traveling Anglo-Saxon to see how fēowertēne niht means “fourteen nights.”
English also has a “one-week” equivalent to fortnight: sennight. Can you guess what the sen- in sennight means? That’s right: seven. Sennight, for a “period of seven days and nights,” is archaic, supplanted by the word week. But, words like sennight and fortnight appear to be a leftover from ancient Germanic calendars, which were known to reckon time not by days—but by nights.
Who uses fortnight?
To many speakers of American English, a fortnight sounds like it comes from a time long ago—perhaps even when fur-clad warriors huddled before fires at night within forts built out of tall, wooden pikes. (Winterfell, anyone?)
But, fortnight is very useful, which is why it still has currency in British English and other forms of English around the world. Consider the words biweekly and bimonthly. Biweekly can mean “every two weeks.” So can bimonthly, if you take “every two weeks” as “twice a month.” But, biweekly can also mean “twice a week,” and bimonthly, “every two months.” Still keeping count with us?
Enter fortnightly, which offers a welcome workaround to the ambiguity of biweekly and bimonthly. If your employer tells you, as they may in the UK and around the world, that you’ll get paid fortnightly, you know you can expect that paycheck every two weeks. If your doctor tells you to take a medication fortnightly, you know you should take it every two weeks. If a teacher says you will have fortnightly quizzes in class … we think you get the idea.
But wait, why isn’t fortnight spelled “fourtnight”?
And why isn’t forty spelled” fourty,” for that matter?
The answer to this question all comes down how variable English spelling has been over centuries. Fortnight was spelled fourtenight in Middle English along with furtenight, fowrtnight, and many other forms.
One of our lexicographers weighed in why forty, though based on four, lacks a U:
The answer to this is one about spellings and which ones “make it” and which ones don’t. The word forty has had no less than 26 spellings over its lifetime, from Old English féowertig, féowurtig, and feuortig to Middle English (many more spellings) to the present day. Over the past 1000 years, these variant spellings have fought it out, and forty, introduced in the 16th century, has won the day. For the moment.
About that Fortnite …
OK, we do see a lot of searches for Fortnite on Dictionary.com, too. No, it’s not in our dictionary, but we can say that Fortnite is apparently named after the online game’s “Save the World” mode, for which players construct forts and other structures to protect against monsters who invade … at night. Hence, nite—an informal, but long-running spelling of night.