Or search: lengthwise
3 Syllables: SUU
functionally, nationally, rationally, usually
4 Syllables: SUUU
criminally, humorously, ludicrously, marginally, nominally, personally
4 Syllables: USUU
conditionally, exceptionally, originally, proportionally, provisionally, traditionally
5 Syllables: USUUU
Additionally, conventionally, diagonally, gratuitously, intentionally, occasionally, professionally
5 Syllables: UUSUU
educationally, unconditionally, unintentionally
6 Syllables: UUSUUU
constitutionally

Found 27 words across 6 groupings.