'frequently' originates from Latin, specifically the word 'frequentia,' where 'frequent-' meant 'crowded or repeated.' 'Checked' comes from Old French 'eschequier,' meaning 'to inspect or verify.'

'frequentia' transformed into the Old French 'frequent,' and eventually became the modern English word 'frequent.' 'Eschequier' evolved into the Middle English 'chekken,' leading to the modern English 'check.'

Initially, 'frequent' meant 'crowded or repeated,' and 'check' meant 'to inspect or verify.' Over time, 'frequently-checked' evolved to mean 'regularly examined.'