'frequently-paired' originates from the combination of 'frequent' and 'pair', where 'frequent' means 'occurring often' and 'pair' means 'two things that are similar or go together'.

'frequent' and 'pair' have been used in English since the Middle Ages, evolving from Latin and Old French origins respectively.

Initially, 'frequent' meant 'crowded' and 'pair' meant 'two of a kind', but over time, they evolved to mean 'occurring often' and 'two things that go together'.