/ Dictionary / Index S secondary xylem: Meaning and Definition of Find definitions for: sec'ondary xy'lem Pronunciation: [key] xylem derived from the cambium during secondary growth. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. secondary wave second axiom of countability Related Content Daily Word Quiz: loathe Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language