verb
-grades; -graded; -grading
[+ obj] :to make (something) better by including the most recent information or improvements
[no obj] :to choose to have or use something more modern, useful, etc. - often + to
to get something (such as a seat on an airplane or a room in a hotel) that is better than what you had originally - often + to; [no obj]
[+ obj] :to give (someone or something) a higher rank or grade - often + to
noun
plural -grades
[count] an area or surface that goes upward :an upward slope
an occurrence in which one thing is replaced by something better, newer, more valuable, etc.
US