The Collaborative International Dictionary of English v.0.48:

Hen \Hen\, n. [AS. henn, hen, h[ae]n; akin to D. hen, OHG.
   henna, G. henne, Icel. h?na, Dan. h["o]na; the fem.
   corresponding to AS. hana cock, D. haan, OHG. hano, G. hahn,
   Icel. hani, Dan. & Sw. hane. Prob. akin to L. canere to sing,
   and orig. meaning, a singer. Cf. Chanticleer.] (Zool.)
   The female of the domestic fowl; also, the female of grouse,
   pheasants, or any kind of birds; as, the heath hen; the gray
   hen.
   [1913 Webster]

   Note: Used adjectively or in combination to indicate the
         female; as, hen canary, hen eagle, hen turkey, peahen.
         [1913 Webster]

   Hen clam. (Zool.)
   (a) A clam of the Mactra, and allied genera; the sea clam
       or surf clam. See Surf clam.
   (b) A California clam of the genus Pachydesma.

   Hen driver. See Hen harrier (below).

   Hen harrier (Zool.), a hawk (Circus cyaneus), found in
      Europe and America; -- called also dove hawk, henharm,
      henharrow, hen driver, and usually, in America, marsh
      hawk. See Marsh hawk.

   Hen hawk (Zool.), one of several species of large hawks
      which capture hens; esp., the American red-tailed hawk
      (Buteo borealis), the red-shouldered hawk (Buteo
      lineatus), and the goshawk.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hen
    n 1: adult female chicken [syn: hen, biddy]
    2: adult female bird
    3: flesh of an older chicken suitable for stewing
    4: female of certain aquatic animals e.g. octopus or lobster

Moby Thesaurus II by Grady Ward, 1.0:

82 Moby Thesaurus words for "hen":
   Bantam, Jane, Partlet, banty, barn-door fowl, barnyard fowl, biddy,
   bird, bitch, bossy, broad, broiler, brood mare, brooder,
   broody hen, capon, chanticleer, chick, chickabiddy, chicken,
   chicky, cock, cockerel, cow, dame, doe, doll, domestic fowl, drake,
   duck, duckling, dunghill fowl, ewe, ewe lamb, filly, fowl, fryer,
   game fowl, gander, gobbler, goose, gosling, guinea cock,
   guinea fowl, guinea hen, gyp, heifer, hen turkey, hind, jenny,
   lioness, mare, minx, nanny, nanny goat, partlet, peahen, poulard,
   poult, poultry, pullet, roaster, roe, rooster, setting hen,
   she-bear, she-goat, she-lion, skirt, slut, sow, spring chicken,
   stewing chicken, tigress, tom, tom turkey, tomato, turkey,
   turkey gobbler, turkey-cock, vixen, wench



Easton's 1897 Bible Dictionary:

Hen
   common in later times among the Jews in Palestine (Matt. 23:37;
   Luke 13:34). It is noticeable that this familiar bird is only
   mentioned in these passages in connection with our Lord's
   lamentation over the impenitence of Jerusalem.


Hitchcock's Bible Names Dictionary (late 1800's):

Hen, grace; quiet; rest