The Collaborative International Dictionary of English v.0.48:
Hatch \Hatch\, n. [OE. hacche, AS. h[ae]c, cf. haca the bar of a
door, D. hek gate, Sw. h[aum]ck coop, rack, Dan. hekke
manger, rack. Prob. akin to E. hook, and first used of
something made of pieces fastened together. Cf. Heck,
Hack a frame.]
1. A door with an opening over it; a half door, sometimes set
with spikes on the upper edge.
In at the window, or else o'er the hatch. --Shak.
2. A frame or weir in a river, for catching fish.
3. A flood gate; a sluice gate. --Ainsworth.
4. A bedstead. [Scot.] --Sir W. Scott.
5. An opening in the deck of a vessel or floor of a warehouse
which serves as a passageway or hoistway; a hatchway;
also; a cover or door, or one of the covers used in
closing such an opening.
6. (Mining) An opening into, or in search of, a mine.
Booby hatch, Buttery hatch, Companion hatch, etc. See
under Booby, Buttery, etc.
To batten down the hatches (Naut.), to lay tarpaulins over
them, and secure them with battens.
To be under hatches, to be confined below in a vessel; to
be under arrest, or in slavery, distress, etc.