The phrase "plow under" typically refers to the act of burying something, particularly vegetation or crops, under soil. Synonyms for this phrase could include "bury," "cover," "conceal," "hide," "entomb," "inter," or "submerge." Burying crops or other organic materials is often done for the purpose of fertilization or as a means of reducing waste. In agricultural contexts, the practice of plowing under crops is known as green manuring or cover cropping. These practices help to improve soil health, increase nutrient levels, and reduce erosion. Synonyms for "plow under" might depend on the specific context in which the term is being used.