Jack-o'-lantern

Jack-o'-lanterns were pumpkins which had designs carved into them for Halloween, most commonly faces. Candles were put inside the carved pumpkins to make the designs visible at night. The heads of the Hervoken resembled jack-o'-lanterns. (PROSE: Forever Autumn)

History
Before humanity developed on Earth, a damaged Hervoken ship crashed into the planet, embedding itself in what would later be New England. The Hervoken slept for thousands of years while a tiny speck of their consciousness influenced humanity to perceive the Hervoken as legends. Through this, it became traditional to carve faces into pumpkins so that they resembled Hervoken.

In 2008, the citizens of Blackwood Falls decorated their front porches with jack-o'-lanterns. Many shops, including Tozier's Costume Emporium, also decorated their storefronts with carved pumpkins. (PROSE: Forever Autumn)

When Zargofly and Zarkon tried to invade Texas, the Eleventh Doctor and Amy Pond harvested and carved pumpkins into jack-o'-lanterns to trick them into thinking that humans cut off and hollowed out the heads of their enemies. (COMIC: The Trick)

On a 1 November in the early 21st century, an alien used a perception filter to make its ship appear to be a pile of Halloween paraphernalia, including jack-o'-lanterns. (PROSE: The Night After Hallowe'en)

On the Halloween in which the Cerebravores attacked New York City, one New York news station had a banner at the bottom of their screen with a jack-o'-lantern next to the message, "Happy Halloween New York City". (COMIC: Revolutions of Terror)