ADJUSTMENT definition: 1. a small change: 2. the ability to become more familiar with a new situation: 3. a small…. Learn more. The meaning of ADJUSTMENT is the act or process of adjusting. How to use adjustment in a sentence. Learn the meaning and usage of the word adjustment in different contexts, such as mechanics, psychology, economics, and insurance. Find synonyms, translations, and related terms for adjustment. Find 1 594 synonyms for Adjustment to improve your writing and expand your vocabulary.