adj. 1 higher (up), loftier, topmost, more elevated, uppermost Air is less dense in the upper parts of the atmosphere Our flat is on an upper floor. Her best notes are sung in the upper register. 2 higher, upland, more elevated; (more) northerly, northern We visited the cataracts on the upper reaches of the Nile We spent the holiday in upper Canada. 3 later, more recent These strata were laid down in the Upper Cretaceous period 4 upper case. capital letter(s), capital(s), majuscule (letters or characters) The heading ought to be in upper case 5 upper crust. upper class, élite, aristocrats, nobles, blue bloods, wealthy, US Four Hundred Gregory thinks of himself as a member of the upper crust and won't associate with us 6 upper hand. advantage, control, authority, power, sway, superiority, supremacy, command, dominance, ascendancy, Colloq edge Purvis kowtows to whoever has the upper hand
n. 7 on (one's) uppers. poor, indigent, destitute, poverty-stricken, Colloq broke Stanley has been on his uppers since losing his job