Or search: keen, acute, incisive, piercing, lancinate, perceptive, penetrating, discriminating
2 Syllables: SU
childlike, cyanide, Einstein, eyesight, finite, guidelines, highlight, hindsight, lifelike, lifestyle, lifetime, likewise, limelight, nisi, pipeline, quinine, Sinai, skyline, stylized, twilight, wildlife

Found 21 words across 1 groupings. Skipped 1 excess word of a similar stem.