I used to work for the Oxford English Dictionary. I got the very first word to define. It’s not just the indefinite article, it has seventy-one distinguishable uses, spread over twelve centuries. “A-gnostic”, “a-new”, “a-bed”, “a-rise”, “a-down-a-down-day”...
You know how, if you say word over and over, the sense goes out of it? After year of research, condensed into four pages of intense scholarship, I couldn’t bear seeing it.
When I retired, they gave me present, old book, “The Perfection of Wisdom In One Letter”. And the letter? “AAAAAAAAAAAAAAAA!!!”
So I emigrated to Russia. They don’t have word for it.