PSE Advent Calendar 2021 (Day 1): La laa laaaaaa laa la Christmas

This puzzle is part of the Puzzling StackExchange Advent Calendar 2021. The accepted answer to this question will be awarded a bounty worth 50 reputation.

Next Door >

...la laaa laaa laaa la la:

TASK: An odd number of related things (greater than 50) have been hidden horizontally, vertically and diagonally in the grid above. Each 'thing' may be a single word or consist of multiple parts (e.g. a person's full name), and is at least 4 letters in length. Your task is to find all of the hidden things, explaining their relevance to the Christmas-themed construction of this puzzle. The leftover letters should help you identify one final 'thing' that this puzzle would be incomplete without (which should hopefully become obvious once you crack what is going on here...).

Important caveat: One 5-letter thing appears backwards within the letters of one 12-letter thing found diagonally within the grid. There are no other (intentional) cases of things appearing entirely as substrings of other things in the grid, either forwards or backwards.

Text version of the wordsearch (for copy-paste purposes):

WERIUGAMTTAMOTIMABUSE
ACHAMBERKCABREHTAELEZ
HHRJNELLUMYRRALRILLNT
SAPHILCOLLINSPANEEEOR
DRKBETWEENVUIRNWNLWJE
ALITUNDRAOGHNESGOHIAC
BECRGAHDRNMGBGYODELTO
KWHPUOEIOENEEKPNIEAAL
CAEAUMSITYNMCEIRRPHKE
ITNSOYPTLNEIRDSNOOTYP
NTERNMEEANMDAAUQRAFAO
OSTOANVITROLAJORDANRU
OTTHAEDREERACHAPMANOL
MFCJESUSCHRISTENGISGE
HABEWICKSNCOSCOROBAET
TRLAUNDRYKARENHAUERRP
ICPROFESSIONEDARTDPTE
KIYESMIWRETEPYUAIARYA
DAMYDOWDENCGETXMNGLLB
LNRDOOWTEELFKCIMAAURN
EEPURITYREECETATUMRGU
ILJEFFAGOOSDELAPRIMER
FSKERMANORYBLACAILLES
OGNIDDEWBLACKSCULLERY

• If we see a dictionary word of 4 letters or more in the grid, is it guaranteed to be one of the related things? I keep finding words of 4 letters exactly and psyching myself out wondering whether they might be false positives. Dec 1, 2021 at 11:40
• @F1Krazy No guarantee - you're looking for a group of 50+ related words that all happen to be 4 letters or longer... It is highly likely that other 4-letter words exist in the grid, either as substrings of words in the connected group or entirely independently. Finding longer words should help guide you in the right direction :)
– Stiv
Dec 1, 2021 at 11:47
• I have a hunch, purely going off of theme, that the number of hidden things is 77 :)
– xnor
Dec 1, 2021 at 12:09

The completed word search:

There are 77 clues following the 12 Days of Christmas rhyme. Colors in the grid indicate the different lines of the rhyme:

• 12 drummers drumming - literally drummers in bands: Keith Moon, Chad Smith, Charlie Watts, Dave Grohl, Roger Taylor, Larry Mullen Jr., Phil Collins, Mick Fleetwood, Micky Dolenz, Evelyn Glennie, Tre Cool, Ringo Starr

• 11 pipers piping - things that have 'Piper' as a prefix or first name: Perabo, Chapman, oilfield, aircraft, gurnard, diagram, Kerman, Halliwell, De la Prim, Laurie, Heidsieck

• 10 lords a-leaping - actual or fictional lords: Farquaad, Jesus Christ, Voldemort, Peter Wimsey, Nelson, Byron, Sugar, Snooty, Lucan, Asriel

• 9 ladies dancing - professional dancers from Strictly Come Dancing: Amy Dowden, Karen Hauer, Janette Manrara, Diane Buswell, Katya Jones, Nadiya Bychkova, Ola Jordan, Oti Mabuse, Nancy Xu

• 8 maids a-milking - different 'types' of maids: chamber, house, nursery, laundry, scullery, kitchen, parlour, between

• 7 swans a-swimming - swan (sub)species: black, tundra, Bewick's coscoroba, whooper, mute, trumpeter

• 6 geese a-laying - people with the nickname 'Goose': Nick Bradshaw, Paul Gaustad, Matt Maguire, Tony Siragusa, Jeff Agoos, Reece Tatum

• 5 golden rings - rings for special occasions: championship, wedding, purity, signet, engagement

• 4 calling birds - synonyms for 'calling': vocation, profession, career, trade

• 3 French hens - French words for chicken-like animals: le poulet, la caille, la dinde

• 2 turtle doves - species of turtles: loggerhead, leatherback

The leftover letters form "a pear partridge tree", or in other words a partridge in a pear tree, the one thing missing from the rhyme and the thing we were looking for.

• You've done phenomenally well here to solve this wordsearch given no word list at all - well done! You can get rid of the worrying 'C' if you notice that you've actually only listed ten pipers here. The last one you need can be found somewhere on the Wikipedia disambiguation page... Then list the letters you have left in order and interpret what you've got. Great job :)
– Stiv
Dec 1, 2021 at 22:02
• @Stiv, thanks. So much for my nice numbered excel lists. I updated my answer Dec 1, 2021 at 22:11
• Nice work - all now present and correct: here's a checkmark for you!
– Stiv
Dec 1, 2021 at 23:06