US adjective 2noun 3forms 1phrases 1 adjective2 •Abbreviation of unserviceable.The radio is US. •Abbreviation of undersize. noun3 •Initialism of the United States: a country in North America.ICANN is based in the US.The Gulf States are the US states bordering the Gulf of Mexico. •Initialism of ultrasonography or ultrasound. •Initialism of unconditioned stimulus. formsUSs Phrases with US come down to usTo survive to the present day; to be extant in some form.