Perturbative refers to a mathematical approach of solving complex problems by breaking them down into simpler, solvable components. Synonyms for perturbative include iterative, recursive, incremental, and approximative. These words describe the step-by-step, incremental nature of perturbative techniques, as each step builds on the previous one to approach a final solution. Other synonyms include analytical, methodical, and speculative, which imply a calculated and deliberate approach to problem-solving. In contrast, non-perturbative approaches, also known as direct or exact methods, attempt to solve complex problems as a whole, without breaking them down into simpler parts. Despite their limitations, perturbative methods remain a powerful tool for tackling complex problems across various disciplines, including physics, engineering, and finance.