Upthrust is a term used in geology to refer to the upward force that causes rocks to rise above the surface of the earth. Synonyms for the word upthrust include uplift, heave, thrust, and elevation. Another synonym is upliftment, which refers to the process of uplift. In addition, the term upthrust can also be used interchangeably with the term uplift, which refers to the process of raising or lifting something up. Other synonyms for upthrust include hoist, boost, and elevate. These words all convey a sense of upward movement and can be used to describe geological or physical processes as well as emotional or psychological states.