surname, attested from late 12c., probably meaning bald head; cf. Wyclif Stye up, ballard, where Coverdale translates Come vp here thou balde heade [2 Kg.2:23-24, where God kills 42 children for making fun of Elijah's lack of hair.]
A slump is a form of mass wasting that occurs when a coherent mass of loosely consolidated materials or rock layers moves a short distance down a slope. Movement is characterized by sliding along a concave-upward or planar surface. Comments.
The term 'slump' is also used to refer to the material that breaks off in a slumping slide. Slumps are sometimes caused by clear cutting on unstable soils, and the sagging and rotational movement of the mass of soil and rock is due in part to water infiltration and lubrication of clay-rich soils below.