The American Heritage® Dictionary of the English Language, 4th Edition
n. A rectangular, often tapering stone post bearing a carved head or bust, usually of Hermes, used as a boundary marker in ancient Greece and for decorative purposes in later periods.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a statue consisting of a squared stone pillar with a carved head (usually a bearded Hermes) on top; used in ancient Greece as a boundary marker or signpost
Word Usage
"But then I stepped back, saw the name 'herm' and suddenly it wasn't so unbelievable."