/ Dictionary / Index Y youth-and-old-age: Meaning and Definition of Find definitions for: youth-and-old-age Pronunciation: (yth'un-ōld"āj', -und), [key] — n. a stiff-growing, erect composite plant, Zinnia elegans, of Mexico, having large, solitary flowers with yellow-to-purple disks and usually red rays. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. youth youthen Related Content Daily Word Quiz: ontiguous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language