approximately

This word signals a deliberate move away from precision to provide a helpful estimate. It is the standard choice for technical, scientific, or formal reports where a precise figure is unknown or unnecessary, but a rough range is required to maintain credibility. While similar to roughly or about, this term carries a polished, professional tone. It suggests a calculated estimate rather than a casual guess, making it the preferred term in academic writing or official documentation to describe measurements, durations, or populations.