-er 1suff.1. a. One that performs a specified action: swimmer.b. One that undergoes or is capable of undergoing a specified action: broiler.c. One that has: ten-pounder.d. One that is associated or involved with: banker.2. a. Native or resident of: New Yorker.b. One that is: foreigner.[Middle English, partly from Old English -ere (from Germanic *-?rjaz, from Latin -?rius, -ary), partly from Anglo-French -er (from Old French -ier, from Latin -?rius) and partly from Old French -ere, -eor; see -or1.]-er 2suff. Used to form the comparative degree of adjectives and adverbs: darker; faster.[Middle English, from Old English -re, -ra.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.-er suffix forming nouns 1. a person or thing that performs a specified action: reader; decanter; lighter. 2. a person engaged in a profession, occupation, etc: writer; baker; bootlegger. 3. a native or inhabitant of: islander; Londoner; villager. 4. a person or thing having a certain characteristic: newcomer; double-decker; fiver. [Old English -ere; related to German -er, Latin -?rius]-er suffix forming the comparative degree of adjectives (deeper, freer, sunnier, etc) and adverbs (faster, slower, etc) [Old English -rd, -re (adj), -or (adv)]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014er (?, ?r) interj. (used to express or represent a pause, hesitation, uncertainty, etc.) ER 1. efficiency report. 2. emergency room. Er Chem. Symbol. erbium. -er1 , a noun-forming suffix, added to nouns to form words designating persons from the object of their occupation or labor (hatter; moonshiner; roofer), or from their place of origin or abode (Icelander; southerner), or designating persons or things from some special characteristic or circumstance (double-decker; fourth-grader; tanker; teenager). When added to verbs, -er1 forms nouns denoting a person, animal or thing that performs or is used in performing the action of the verb ( baker; eye-opener; fertilizer; pointer; teacher). Compare -ier 1, -yer.[Middle English -er(e), representing Old English -ere agentive suffix (c. Old High German -?ri, Gothic -areis