'America-leaning' originates from Modern English, combining 'America' (ultimately named after the Italian explorer Amerigo Vespucci) with the participial/adjectival element '-leaning', where 'lean' meant 'to incline or slope'.

'America' entered English in the early 16th century via the Latinized form 'America' (from the Italian form referring to Amerigo Vespucci). 'Lean' comes from Old English (e.g. 'hlēanian'/'hleonian') meaning 'to bend or incline'. The compound 'America-leaning' is a contemporary English coinage formed by compounding and using the '-ing' participial/adjectival form.

Initially formed to mean 'inclining toward America' in a literal compositional sense, it has come to be used broadly to describe an attitude, policy, or cultural orientation that favors or is sympathetic to the United States.