'American-looking' is formed by combining 'American' (from 'America', named after the explorer Amerigo Vespucci) and the present-participle adjective-forming element 'looking' (from the verb 'look').

'America' was named after the Italian explorer Amerigo Vespucci in the early 16th century; from this came the adjective 'American' in English. The use of '-looking' as a compound-forming element (meaning 'having the appearance of') is a productive formation in modern English, producing compounds like 'child-looking' or 'American-looking'.

Initially, 'American' meant 'of or relating to America' and 'look' meant 'appear'; together they have meant 'appearing to be American' in modern usage with little shift in core meaning.