The Adirondacks are a range of mountains which run through from New York state across the border into Canada.
They were given their name in 1838 by Ebenezer Emmons, an American geologist. The word carries stress on the third syllable: Adirondacks - which isn't how I would have thought it was pronounced...! (Although I pronounce adonirack with the stress on the same third syllable.)
The word is an Anglicized version of the Mohawk ratirontaks, meaning "they eat trees", a derogatory name which the Mohawk historically applied to neighboring Algonquian-speaking tribes. By 1634, the word was being used by the Mohawks, when speaking among the Dutch, to refer to French and English. The Dutch transliterated the word Aderondackx at that time.
I didn't mean to get sidetracked onto the geography of a particular area in this post, but rather to mention Muskoka chairs. These chairs are sometimes known as Adirondack chairs (or even Adirondak, if you follow the quirky spelling of the area). The Muskoka comes from the municipality of Muskoka, Ontario a cottage country area north of Toronto.
The Adirondack or Muskoka chair was designed by Thomas Lee while he was on holiday in 1903 - it's the sort of thing you do either because you find that you need something to stimulate your brain while on holiday or because there happens to be nothing comfortable to sit on outside. (When I say 'you' I really mean 'one' - since I've never designed a chair on holiday yet...I always hope that there'll be at least something to sit on when I arrive at wherever I'm going to. A holiday without chairs is closer to a nightmare for me. )
The chair wasn't named either Adirondack or Muskoka for the first couple of decades of its existence (and when I say 'the chair' I really mean the innumerable chairs that a certain Harry Bunnell seems to have made - and sold - from Lee's design...without his permission.) They were called Westport plank chairs during that time, since they were made in Westport. Out of planks.
I guess all chairs have names (apropos of the naming of things, it's intriguing to hear the names of the various manoeuvres ice skaters perform in Dancing on Ice) but most of us aren't aware of them. So I hope this post has been informative - and not confusing. Westport/Adirondack/Muskoka. Take your pick!