With the annual spooktacular quickly approaching, Grammar Girl answers a reader's question about the origins of "Hallowe'en"

Allegra Young asked, "What's your take on the apostrophe in 'Hallowe'en'? To use or not to use?"

One early spelling of "Halloween" was "all hallows' even," in which even meant "evening." The "all" and "s" got dropped, "hallows' " and "even" became a closed compound, and the apostrophe took the place of the "v," giving us "Hallowe'en"—just one of many transitional spellings along the way to "Halloween," which the Oxford English Dictionary shows as first appearing in 1786. Other spellings before "Halloween" included "Hallow-e'en," "Alhollon Eue," and "Halhalon evyn."

You can certainly use "Hallowe’en" if you want an 18th-century feel for your party invitations or decorations.

We celebrate Halloween on the last day of October because the holiday was originally tied to the Celtic calendar, in which November 1 was the start of the new year. The Catholic Church later adopted November 1 as All Saints' Day, and October 31 is also sometimes called All Saints' Eve.

Pumpkin photo from Shutterstock.