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definitions

geronto-

a combining form meaning “old age,” used in the formation of compound words: gerontology.
Also especially before a vowel, geront-.

Origin of geronto-

< Greek, combining form representing geront-, stem of gérōn old man
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for geronto-

geronto-

before a vowel geront-

combining form

indicating old agegerontology; gerontophilia

Word Origin for geronto-

from Greek gerōn, geront- old man
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
geronto- in Medicine

geronto-

pref.

Old age:gerontology.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.