Webster's Revised Unabridged Dictionary · 1913

Clamber

Clamber , intransitive verb

[OE clambren, clameren, to heap together, climb; akin to Icelandic klambra to clamp, German klammern. Compare Clamp, Climb.]

To climb with difficulty, or with hands and feet; -- also used figuratively.
The narrow street that clambered toward the mill. — Tennyson

Clamber , noun

The act of clambering. — T. Moore

Clamber , transitive verb

To ascend by climbing with difficulty.
Clambering the walls to eye him. — Shakespeare