1. (n.) An upright, four-sided pillar, gradually tapering as it rises, and terminating in a pyramid called pyramidion. It is ordinarily monolithic. Egyptian obelisks are commonly covered with hieroglyphic writing from top to bottom.

2. (n.) A mark of reference; -- called also dagger [/]. See Dagger.

3. (v. t.) To mark or designate with an obelisk.