A
glissando-type guitar sound used by rockers to
kick out the jams.
To execute the scrape, slide the side of the pick along a string or two, up or down a bunch of frets. This creates a metallic vibrating noise -- TSZHHoooooOOoooomm. This invariably sounds better when highly distorted and immediately followed by a crushing guitar solo.
Used to great effect by many a screamin' guitar player; more common during the glam days than it is now. However, the pick scrape can be overused: see for example Jejune's album This Afternoon's Malady, where a fancy harmonic pick scrape precedes every verse, chorus, and solo.