Additionally rhymes with:
traditionally, conditionally, traditionally, unconditionally, conditionally, nutritionally, traditionally, unconditionally, conditionally, congressionally, constitutionally, conventionally, educationally, exceptionally, fractionally, functionally, generationally, institutionally, intentionally, internationally, irrationally, nationally, nutritionally, operationally, professionally, proportionally, rationally, rotationally, traditionally, unconditionally, unconstitutionally, unintentionally
Additionally sounds like:
additional, atmel, atonal, attitudinal, autumnal