(shak) noun
A rude cabin, as of logs.
—shack up Slang
1. To live together and co-habit: said of unmarried persons.
2. To live or stay, usually briefly, at a specific place. [? <dial. Sp. (Mexican) jacal a wooden hut <Nahuatl xacalli; prob. infl. by RAMSHACKLE]

(shak) noun
1. Fallen acorns or nuts of any kind; mast.
2. Any bait picked up at sea, as dead sea birds, refuse fish, etc.: distinguished from bait regularly carried or newly caught: also shack bait.
3. A catch of miscellaneous, unsorted fish. [<shack, v., dial. var. of SHAKE]

(shak) noun
A slow trot: also shack gait.
—v.t. To go at a slow trot. [Short for shack-rag, var. of shake-rag a vagabond, a worthless horse <SHAKE + RAG²]

(shak) v.t.
To go after; retrieve. [Origin unknown]