accurate
"Accurate" is a straightforward but very useful adjective. It has one core meaning, but it applies across many different situations — from facts and measurements to descriptions and predictions.
In science, math, or any technical field, accurate means that a measurement or calculation is very close to the true value — not just roughly right, but exactly right. Imagine a scale that shows your exact weight, not an approximate one. That scale is accurate.
science / technical · Modern, widely used
The thermometer gave an accurate reading of 37.2 degrees.
For this experiment, you need accurate measurements of each ingredient.