ADVERB (4)

1. at or on or to the masthead or upper rigging of a ship;
- Example: "climbed aloft to unfurl the sail"

2. upward;
- Example: "the good news sent her spirits aloft"

3. at or to great height; high up in or into the air;
- Example: "eagles were soaring aloft"
- Example: "dust is whirled aloft"

4. in the higher atmosphere above the earth;
- Example: "weather conditions aloft are fine"

The Collaborative International Dictionary of English v.0.48:

Aloft \A*loft"\ (?; 115), adv. [Pref. a- + loft, which properly
   meant air. See Loft.]
   1. On high; in the air; high above the ground. "He steers his
      flight aloft." --Milton.
      [1913 Webster]

   2. (Naut.) In the top; at the mast head, or on the higher
      yards or rigging; overhead; hence (Fig. and Colloq.), in
      or to heaven.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Aloft \A*loft"\, prep.
   Above; on top of. [Obs.]
   [1913 Webster]

         Fresh waters run aloft the sea.          --Holland.
   [1913 Webster]

WordNet (r) 3.0 (2006):

aloft
    adv 1: at or on or to the masthead or upper rigging of a ship;
           "climbed aloft to unfurl the sail"
    2: upward; "the good news sent her spirits aloft"
    3: at or to great height; high up in or into the air; "eagles
       were soaring aloft"; "dust is whirled aloft"
    4: in the higher atmosphere above the earth; "weather conditions
       aloft are fine"

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "aloft":
   aboard, above, abovestairs, afloat, airward, all aboard, aloof,
   athwart the hawse, athwarthawse, aye, before the mast, high,
   high up, in flight, in sail, in the air, in the clouds, on board,
   on board ship, on deck, on high, on shipboard, on stilts,
   on the peak, on tiptoe, over, overhead, skyward, straight up,
   tiptoe, to the zenith, topside, up, upstairs, upward, upwards