余量

remnant / leftover / tolerance (i.e. allowed error)

to measure

capacity / quantity / amount / to estimate / abbr. for 量詞|量词[liang4 ci2], classifier (in Chinese grammar) / measure word

surname Yu

(archaic) I / me / variant of 餘|余[yu2], surplus

extra / surplus / remaining / remainder after division / (following numerical value) or more / in excess of (some number) / residue (math.) / after / I / me