Source : Webster's Revised Unabridged Dictionary (1913)

Midgard \Mid"gard`\, n. [Icel. mi[eth]gar[eth]r.] (Scand. Myth.)
   The middle space or region between heaven and hell; the abode
   of human beings; the earth.

Midgard \Mid"gard\ (m[i^]d"g[aum]rd), n. Also Midgarth
\Mid"garth\ (-g[aum]r[th]), Mithgarthr \Mith"garthr\ (Icel.
   m[-e][th]"g[aum]r[th]r'). [Icel. mi[eth]gar[eth]r.] (Teut.
   Myth.)
   The middle space or region between heaven and hell, the abode
   of human beings; the earth.

Source : WordNet®

Midgard
     n : (Norse mythology) the abode of humans in Norse mythology