'small-built' originates from the combination of 'small' and 'built', where 'small' meant 'of limited size' and 'built' referred to 'the form or structure of a person's body'.

'small' and 'built' have been used in English since the Middle Ages, and their combination into 'small-built' is a more modern usage to describe physique.

Initially, 'small' and 'built' were used separately to describe size and structure, but over time they combined to specifically describe a compact physique.