/ Dictionary / Index A alkaline: Meaning and Definition of Find definitions for: al•ka•line Pronunciation: (al'ku-līn", -lin), [key] — adj. Chem. of or like an alkali. containing an alkali. having the properties of an alkali. having a pH value greater than 7. Cf. acid (def. 5c). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: alkaline (Thesaurus) alkalimeter alkaline earth Related Content Daily Word Quiz: tactful Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language