Winter Bash 2021 hats explained

Question

For carrying on the tradition, here is a list of the 'etymology' for the Winter Bash 2021 hats. Everything about the naming (whether related to Stack Exchange mechanics, memes, or anything else that isn't obvious to most readers) can be found here. What may be obvious to you (because you're a game expert, or a native English speaker) may not be obvious to other users. For pictures and a list of criteria, see the Winter Bash 2021 Hat List 😷 🎓 instead.

The list is a community wiki; feel free to edit it if you have more information about a hat. Please keep the list in alphabetical order for easier searching. If you like to do some research, some hats have been featured in earlier editions, so you might be able to find more information in the previous installments:

Year	Question
2020	Winter Bash 2020 hat names & references explained
2019	no entry since all hats were reruns
2018	Winter Bash 2018 hat names
2017	Winter Bash 2017 hatymology
2016	A list of what each of the Winter Bash 2016 hats are named after
2015	Is there a list of what each of the Winter Bash hats is named after?

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^{Copied from Glorfindel's 2020 post.}

Answer 1

Regular hats

Hat	Explanation
Plus 44	Reference to +44 band.
Soapbox	Reference to the English idiom "to get on a soapbox," meaning to publicly make an opinionated speech, analogous to starting a discussion on Meta.

Secret hats

• E-pic: Its trigger is somewhat related to Gadsby.
• Kitsune: Intelligent foxes in Japanese folklore.
• Manual Key: Stack Overflow 'The Key' prank.
• Matryoshka: Reference to Russian nested dolls.