Synonyms for Alkaline:

adj.

being basic, not acid (chemically) (adjective)
antacid, caustic, soluble, bitter, Neutralizing, salty, acrid, alkalescent.

n.

alkaloid, catalytic, corrosive, anaerobic, chemical equation, concentrated, active, aerobic. alkali (noun)
bitter, chemical, soluble, caustic, Neutralizing, salty, acrid, antacid.
alkaline (noun)
alkalescent, base-forming, alcalescent, basic, alkalic.

Other synonyms:

alkaloid, catalytic, anaerobic, corrosive, concentrated, chemical equation, aerobic. chemical. active. briny
salty.
corrosive
caustic.
Other relevant words:
anaerobic, aerobic, chemical, basic, caustic, active, bitter, corrosive, salty, concentrated, catalytic, soluble, acrid, antacid, alkaloid, Neutralizing.

Usage examples for alkaline

  1. An Alkaline Reaction is the turning of red litmus blue. – An Introduction to Chemical Science by R.P. Williams
  2. Potash is the best alkaline agent to use. – The Dyeing of Woollen Fabrics by Franklin Beech
  3. Human milk is alkaline and even if kept for a considerable time it shows little tendency to become sour. – The Mother's Manual of Children's Diseases by Charles West, M.D.