[1] : The Collaborative International Dictionary of English v.0.48

ladder \lad"der\ la^d"d~er, n. oe. laddre, as.
   hl=aeder, hl=aedder; akin to ofries. hladder, ohg.
   leitara, g. leiter, and from the root of e. lean, v.
   root40. see lean, v. i., and cf. climax.
   1. a frame usually portable, of wood, metal, or rope, for
      ascent and descent, consisting of two side pieces to which
      are fastened cross strips or rounds forming steps.
      1913 webster

            some the engines play,
            and some, more bold, mount ladders to the fire.
                                                  --dryden.
      1913 webster

   2. that which resembles a ladder in form or use; hence, that
      by means of which one attains to eminence; as, to climb
      the corporate ladder.
      1913 webster +pjc

            lowliness is young ambition's ladder. --shak.
      1913 webster

   fish ladder. see under fish.

   ladder beetle zool., an american leaf beetle chrysomela
      scalaris. the elytra are silvery white, striped and
      spotted with green; the under wings are rose-colored. it
      feeds upon the linden tree.

   ladder handle, an iron rail at the side of a vertical fixed
      ladder, to grasp with the hand in climbing.

   ladder shell zool., a spiral marine shell of the genus
      scalaria. see scalaria.
      1913 webster
see also:
lean climax fish ladder fish ladder beetle chrysomela scalaris 
ladder handle ladder shell scalaria 

[2] : WordNet (r) 2.0

ladder
     n 1: steps consisting of two parallel members connected by rungs;
          for climbing up or down
     2: ascending stages by which somebody or something can
        progress; "he climbed the career ladder"
     3: a row of unravelled stitches; "she got a run in her
        stocking" syn: run, ravel
     v : come unraveled or undone as if by snagging; "her nylons were
         running" syn: run
see also:
run ravel 

[3] : Easton's 1897 Bible Dictionary

ladder
   occurs only once, in the account of jacob's vision gen. 28:12.
   

Ladder >> L Words
Ladder, definition of term: Ladder
ladder_pag1.html

Jacobs Ladder >> J Words
Jacobs Ladder, definition of term: Jacobs Ladder
jacobs+ladder_pag1.html

Fish Ladder >> F Words
Fish Ladder, definition of term: Fish Ladder
fish+ladder_pag1.html