Which Christmas carol contains an entire line of 2 letter nonsense words?

Which Christmas carol contains an entire line of two-letter nonsense words? The answer is “Deck the Halls,” with its famous “fa la la la la, la la la la” refrain.

The carol’s English lyrics were written by Scottish musician Thomas Oliphant and published in 1862. They were fitted to a much older Welsh melody associated with “Nos Galan,” a traditional New Year’s song dating back to the eighteenth century. The repeated “fa-la-la” syllables are not meant to convey literal meaning; they function as a lively musical refrain between the lyrical lines.

The song is often called “Deck the Hall” in older versions, while “Deck the Halls” is the familiar modern title. Lyrics also vary between “Troll the ancient Yuletide carol” and “Troll the ancient Christmas carol,” depending on the edition. Those variations do not change the identifying nonsense-word line.

A common mix-up is assuming that every repeated vocal syllable in a holiday song is unique to this carol. “Fa-la-la” appears elsewhere, but “Deck the Halls” is the standard Christmas carol recognized for an entire refrain built from these short nonsense words.