Or search: sedative, ataractic, depressant, tranquilizing, tranquillising
3 Syllables: SUU
realising, realizing
4 Syllables: SUUU
analyzing, civilizing, equalizing, fertilizing, generalizing, mobilizing, moralizing, neutralizing, paralyzing, sanctifying, specializing, stabilizing, symbolizing, tantalizing, utilizing
5 Syllables: USUUU
demoralizing

Found 18 words across 3 groupings.