'macadamize' originates from Scots/English, specifically the noun 'macadam' named after the surname 'McAdam' (John Loudon McAdam), where 'Mac-' meant 'son of' and 'Adam' was a personal name.

'macadamize' changed from the noun 'macadam' (the road-surface named for McAdam) with the addition of the English verb-forming suffix '-ize' in the 19th century to form the modern verb 'macadamize'.

Initially it referred specifically to treating roads by McAdam's method of compacted broken stone; over time it has come to mean more generally to surface or pave a road with crushed stone or similar materials.