Beaver Moon
Two explanations are in circulation and they point in opposite directions. One is that November is when beavers are most visible finishing their lodges and dams before the water freezes. The other is that it was the month to set beaver traps, while the animals were in thick winter coat and the waterways were still open.
Where the name comes from
The trapping version is the more commonly printed one, and it is worth noticing what it implies: commercial beaver trapping on that scale is the North American fur trade, which is a colonial industry. A name that originates there cannot also be an ancient Indigenous one, whatever the list it appears in says. This is the entry where the almanac's blanket attribution comes apart most visibly.
Also called Frost Moon, Mourning Moon.
Old Farmer's Almanac; fur trade chronology from standard histories