Or search: shady, shaded, umbrageous
2 Syllables: SU
backbone, Blackstone, cathode, facto, Gladstone, hallowed, macro, shadow
3 Syllables: USU
foreshadowed, tobacco, unhallowed
4 Syllables: UUSU
Colorado, overshadow

Found 13 words across 3 groupings. Skipped 2 excess words of a similar stem.