surreptitiously.

In a way intended to avoid being noticed, often because permission or approval is doubtful.

Use it for

Words that belong together

• glance surreptitiously
• leave surreptitiously

On the page

He surreptitiously checked the sealed envelope while the others examined the map.

Usage notes

Primary category: literary / elevated general. Forms: Invariable adverb. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Commonness: moderately common.