Fixation rhymes with:
annexation, indexation, relaxation, subluxation, taxation, alsatian, annexation, cessation, compensation, condensation, conversation, dispensation, indexation, relaxation, sensation, subluxation, taxation
Fixation sounds like:
facedown, faction, fasten, faustian, faustina, faustine, faustino, festoon, fiction, fightin', fochtman, fuston