noun / verb
tar
TAR/tɑːr/
A thick black coating substance.
The open metal pail holds thick, sticky black tar.

Etymology
Old English teoru referred to tar, pitch, and resin—the sticky material associated with certain trees. This connects the modern substance with its longstanding uses in sealing and caulking.
In context
as if he had been poured in tar he lies on a pillow of turf and seems to weep the black river of himself
More examples
- Workers tar the wooden posts to protect them from moisture.
- A smear of tar sticks to my boot.
- The freshly tarred roof keeps the rain out.
Forms
tar · tars · tarred · tarring
tarry adjective — Thick, dark, and sticky like tar.