'suspiciously' originates from the Latin word 'suspiciōsus,' where 'sus-' meant 'under' and 'specere' meant 'to look.'

'suspiciōsus' transformed into the Old French word 'suspicios,' and eventually became the modern English word 'suspiciously' through Middle English.

Initially, it meant 'to look under or beneath,' but over time it evolved into its current meaning of 'distrustful or doubtful manner.'