Here's what rhymes with diphteritic.
lytic critic dendritic analytic catalytic parasitic granitic paralytic arthritic impolitic porphyritic zoophytic hemolytic proteolytic syphilitic haemolytic hydrolytic nephritic electrolytic saprophytic encephalitic cenobitic thrombolytic antisemitic coenobitic psychoanalytic fibrinolytic hermaphroditic Words that almost rhyme with diphteritic
acidic juridic philippic bromidic phenotypic terrific civic cystic lyric mystic mimic mythic ballistic citric pacific physic cynic lithic thymic gimmick triptych arrhythmic diptych periwig nitpick specific artistic clinic optimistic rhythmic picnic statistic acrylic autistic cryptic dualistic elliptic idyllic limbic lipstick logistic rabbinic sadistic satiric theistic honorific juristic patristic aphoristic dipstick sophistic sylphic realistic intrinsic stylistic deterministic holistic idealistic journalistic pessimistic prolific simplistic ecliptic horrific ritualistic animistic antiarrhythmic atheistic basophilic egoistic empiric fatalistic futuristic hedonistic metaphysic militaristic monistic chauvinistic egotistic patronymic surrealistic bulimic jingoistic pantomimic pinprick pugilistic nepotistic puristic flyspeck scientific linguistic unrealistic apocalyptic extrinsic heuristic logarithmic mechanistic monolithic naturalistic altruistic capitalistic hydrophilic moralistic opportunistic paternalistic pluralistic socialistic synergistic algorithmic legalistic neolithic novelistic pantheistic polycystic positivistic syllogistic eulogistic shamanistic voyeuristic euphemistic feudalistic inartistic palaeolithic belletristic casuistic nonrhythmic characteristic antagonistic humanistic materialistic monopolistic nonspecific probabilistic hemispheric cataclysmic communistic imperialistic impressionistic monotheistic organismic cannibalistic megalithic polytheistic stratospheric unspecific paleolithic overoptimistic transpacific polyclinic individualistic nationalistic anachronistic narcissistic rationalistic relativistic unscientific carboxylic eosinophilic hieroglyphic oligopolistic uncharacteristic spiritualistic expressionistic nonscientific universalistic sociolinguistic