EER energy efficiency ratio. e’er (??r) adv. Chiefly Literary. ever. [1595?1605] -eer a noun-forming suffix occurring orig. in loanwords from French (buccaneer; mutineer; pioneer) and productive in the formation of English nouns denoting persons who produce, handle, or are otherwise associated with the referent of the base word (auctioneer; engineer; mountaineer; pamphleteer); now frequently pejorative (profiteer; racketeer). Compare -ary, -er2, -ier2. [