My question is simple: Which came first, bunk as in "bunk beds" or "to bunk" as in to find a place to sleep? Most assuredly, the definition of one created the definition of the other by association, however I was wondering if anyone knew which came first.
As I noted in a comment above, Merriam-Webster's Eleventh Collegiate Dictionary (2003) gives 1758 as the date of first occurrence for bunk (noun) and 1840 as the date of first occurrence date for bunk (verb). My edition of the Oxford English Dictionary (1985) gives 1815 as the date of first occurrence for bunk (noun) and 1860 as the date of first occurrence for bunk (verb).
In a Google Books search, the first unambiguous instance of bunk (noun) is from George Washington, “General Orders, Wednesday, March 8, 1780,” in The Writings of George Washington from the Original Manuscript Sources, 1745–1799, volume 18:
The hot season approaching, every possible attention is to be paid to cleanliness in the interior and environs of the camp; Sinks are to be dug without delay. Every fair day the windows and doors of all the huts should be kept open the greatest part of the day, and the beding straw and bunks frequently aired.
In addition, however, an instance of the compound term slaw-bunk may reflect usage as early as 1753 in colonial upstate New York. From Gideon Hawley, Rev. Gideon Hawley’s Journey to Oghquaga, 1753 (July 31, 1794):
Mr. Woodbridge and I with assiduity pursued our way, one after the other, through bushes, and sloughs, water and mire as our guide directed. And at dusk we arrived at the nearest houses between fort Hunter and Schoharry ; but did not put up until we came to what was accounted a publick house, but very unfit for the entertainment of gentlemen strangers. It had only one room. In that room was what is called a slaw-bunk, with a straw-bed, on which we lodged.
Meanwhile the two earliest instances of bunk (verb) that a Google Books search found are from the late 1830s. From John W. Gould, John W. Gould's Private Journal of a Voyage from New York (1838):
[Saturday, June 23d., 1838.] At six P. M. saw J———S——— and A———S——— just from town, with nephews and neices, for fresh air. Gave J——— a cigar. Grew cold, went aboard, ate supper with a great appetite, and bunked on the transom. Couldn't sleep in my berth, because of the "animals."
[Tuesday, June 26th.] At supper, our cat and our boy made their appearance, recovered from sea-sickness. I smoked a cigar ; chatted with the skipper ; thought how Broadway would look by this moon ; sung songs ; grew sentimental ; thought about the girls ; and then bunked on the cabin transom, “afeared of toads” if I entered the berth.
From “The Late John W. Gould,” in The Knickerbocker: Or New-York Monthly Magazine (January 1839):
[Monday, June 25th.] Boxed about off the Hook, in fine style, until one P. M., when a breeze sprung up from W. S. W., which increased to a sneezer. No particular appetite for supper, though not regularly sea-sick. Only felt a little disagreeably. At evening, grew squally and rainy, so I bunked on cabin lockers, and heard the dash of the rain, and the thunder and lightning, and the creaking of the ship, and the tramp of feet, and the quick, loud orders of the captain, without fearing that the ship would fall overboard, and hugging myself with the consciousness that all that was none of my business. Let the old boat burn : I’m a passenger.
Both references are to the same journal written by the same person, though my Google Books search didn’t find the instance of bunked that was quoted in the Knickerbocker article in the Private Journal (it is there, nevertheless).
From the evidence available, it seems very likely that bunk (noun) antedates bunk (verb) by a substantial number of years, though the precise years involved are uncertain.
For a (somewhat related) discussion of the etymological connection between bunk and bunker, see Are “bunk” and “bunker” directly related?.