The Collaborative International Dictionary of English v.0.48:

Jag \Jag\, v. t. [imp. & p. p. Jagged; p. pr. & vb. n.
   Jagging.]
   To cut into notches or teeth like those of a saw; to notch.
   [Written also jagg.]
   [1913 Webster]

   Jagging iron, a wheel with a zigzag or jagged edge for
      cutting cakes or pastry into ornamental figures.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

jagged \jag"ged\ (j[a^]g"g[e^]d), a.
   Having jags; having rough, sharp notches, protuberances, or
   teeth; cleft; laciniate; divided; as, jagged rocks. " Jagged
   vine leaves' shade." --Trench. -- Jag"ged*ly, adv. --
   Jag"ged*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

jagged
    adj 1: having a sharply uneven surface or outline; "the jagged
           outline of the crags"; "scraggy cliffs" [syn: jagged,
           jaggy, scraggy]
    2: having an irregularly notched or toothed margin as though
       gnawed [syn: erose, jagged, jaggy, notched,
       toothed]