The word "guesstimates" implies a rough estimate or a guess. The antonyms for this word are precise, accurate, exact, and calculated. To move away from guesstimates, we must rely on accurate data and calculations. Precision implies a high degree of accuracy and exactitude, while accuracy means correctness or exactness. Calculated refers to a result achieved with a planned and systematic approach. In business and scientific analysis, it is essential to avoid guesstimates as they may lead to wrong assumptions and costly errors. Instead, we should strive for precise and calculated decisions that are based on accurate data and analysis.