猜测 means 'to speculate' or 'to surmise' — forming a tentative opinion or conclusion without complete evidence. The character 猜 (cāi) means 'to guess', often implying intuition or uncertainty, while 测 (cè) means 'to measure' or 'to estimate', adding a sense of assessment or judgment. Together, they emphasize reasoned but unconfirmed inference rather than random guessing.

This verb is commonly used in everyday conversation and writing when people interpret ambiguous situations — for example, deducing someone’s mood, motive, or intentions based on limited clues. It carries a neutral-to-slightly formal register and appears frequently in news reports, psychological discussions, and casual dialogue about uncertain outcomes. Unlike the more casual 猜 (cāi) alone, 猜测 suggests a slightly more deliberate, reflective process — not just a snap hunch, but an informed hypothesis.