[ awl-der ]
/ ˈɔl dər /
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any shrub or tree belonging to the genus Alnus, of the birch family, growing in moist places in northern temperate or colder regions and having toothed, simple leaves and flowers in catkins.
any of various trees or shrubs resembling an alder.



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Origin of alder

before 900; Middle English alder, aller,Old English alor, al(e)r; cognate with Old Norse ǫlr,Middle Low German al(l)er<Germanic *álusṓ; akin to Middle High German alze<Germanic *alū́sō,Old High German elira, erila (German Erle) <Germanic *álisṓ,Middle Low German els(e) <Germanic *alísō, hence Germanic *álus, alísō; compare Polish olcha,Russian olʾkhá<Indo-European dialect *alisā;Lithuanian al̃ksnis,Latin alnus<Indo-European dialect *alsnos

Definition for alder (2 of 2)

[ ahl-der; German ahl-duhr ]
/ ˌɑl dər; German ˈɑl dər /


Kurt [kurt; German koort], /kɜrt; German kʊərt/, 1902–58, German chemist: Nobel Prize 1950.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for alder

/ (ˈɔːldə) /


any N temperate betulaceous shrub or tree of the genus Alnus, having toothed leaves and conelike fruits. The bark is used in dyeing and tanning and the wood for bridges, etc because it resists underwater rot
any of several similar trees or shrubs
Old English alor; related to Old High German elira, Latin alnus
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for alder

[ äldər ]
Kurt 1902-1958

German chemist. He shared a 1950 Nobel Prize for discoveries concerning the structure of organic matter.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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