- At least one local bank website I've gone to today has a banner saying it is closed and uses the word "Juneteenth."
This seems to be reasonable enough to consider it a real word.
Additionally, the term "Emancipation Day" is inaccurate (and therefore obfuscatory) because slavery is still legal and constitutional if you are convicted of a crime. Emancipation doesn't accurately describe the current state unless this is no longer true. I'm going by this dictionary definition of "emancipation": https://www.merriam-webster.com/dictionary/emancipation