l33tness. If something or someone is l33t, it is/they are cool, skilled, neat, or otherwise nifty. Thus, l33tn355 is a measure of how l33t something or someone is.
t3h l33tn355 0f th@7 d00D 15 1/\/(R3D1813!
by Toptomcat November 23, 2003
l337n355 is yeR d3gR33 0f Pwn4g3 and can b3 s0m3th1nG rather c00l.
20 h34dsh0tz 1n 4 r0w is ub3|2 l337n355.
by Matt December 12, 2003