obelisk

noun

1. A tall, square, tapered, stone monolith topped with a pyramidal point, frequently used as a monument.

   “"The clay envelope is Sumerian. It is from the third millennium B.C. It was dug up from the city of Eridu is southern Iraq. The black stele or obelisk is the Code of Hammurabi, which dates from about 1750 B.C.”

   “The Washington Monument is often described as an obelisk, and sometimes even as a "true obelisk," even though it is not. A true obelisk is a monolith, a pylon formed out of a single piece of stone.”

2. (historical)Synonym of obelus.
3. Synonym of obelus.
4. An RNA structure similar to a viroid, with a rod-like secondary structure, which comprises its own phylogenetic group.

verb

1. To adopt the obelisk posture; to point the tip of the abdomen towards the sun.

   “Dragonflies that spend the day in full sun may obelisk to minimize the sunlight striking the body. An obelisking dragonfly looks like it's doing a headstand[…]”