Novelty reindeer antlers
From Tardis Wiki, the free Doctor Who reference
Reindeer antlers made of fabric and attached to a headband were commonly worn at Christmas time.
Wilfred Mott wore two pairs over his hat. (TV: The End of Time)
In an alternate timeline, Wilfred also wore two pairs of fabric antlers on Christmas 2008. Sylvia Noble told him to take them off, but Wilf refused, because "it [was] Christmas". (TV: Turn Left)
On Christmas Day 5343, the Twelfth Doctor was wearing a pair of antlers when he first met Nardole. (TV: The Husbands of River Song)