Here's what rhymes with monotonic.
tonic ionic sonic conic phonic bionic chronic ironic colonic demonic iconic mnemonic sardonic laconic subsonic daemonic acetonic harmonic tectonic chorionic isotonic planktonic platonic catatonic diatonic monophonic avionic embryonic ultrasonic supersonic diachronic hypertonic polyphonic symphonic synchronic telephonic electronic hegemonic ganglionic histrionic hydroponic infrasonic quadraphonic quadrophonic architectonic stereophonic philharmonic pathognomonic microelectronic Words that almost rhyme with monotonic
atomic comic anatomic autonomic genomic diatomic agronomic ergonomic subatomic economic uneconomic astronomic tragicomic taxonomic gastronomic macroeconomic microeconomic socioeconomic topic boric logic toxic folic gothic tropic atopic biotic bardic subtopic hayrick rollick cosmic aortic chaotic erotic garlic neurotic caustic melodic narcotic carbolic idiotic pyloric anabolic anoxic cathodic formic frolic gnostic iambic karmic meiotic meteoric myopic nontoxic robotic cirrhotic homoerotic seraphic strophic chopstick carsick noncaloric shambolic placekick historic symbolic metabolic periodic apostolic aquatic exotic hydraulic biologic caloric despotic episodic geologic hypnotic psychotic systolic isotopic metaphoric necrotic phenolic anarchic basaltic catabolic dialogic euphoric fibrotic hypoxic orthodontic thrombotic antarctic bucolic diabolic heartsick rhapsodic allegoric nonnarcotic alcoholic patriotic antibiotic diastolic isotropic neurologic pathologic ascorbic etiologic hyperbolic metamorphic morphologic parabolic semiotic spasmodic symbiotic synoptic yardstick agnostic cathartic lethargic melancholic pedagogic sclerotic demagogic folkloric hierarchic unpatriotic vitriolic xenophobic acrostic ecologic misanthropic subarctic workaholic macrobiotic sophomoric theosophic subtropic aetiologic chocoholic gynaecologic shopaholic astronautic chocaholic horologic diagnostic philosophic catastrophic cytotoxic histologic macroscopic philanthropic prognostic anisotropic endoscopic immunologic psychologic gynecologic hematologic oligarchic polymorphic psychotropic quixotic telescopic arthroscopic gyroscopic nonalcoholic posthypnotic haematologic seismologic microscopic hydrochloric physiologic prehistoric pharmacologic peristaltic fluoroscopic kaleidoscopic microcosmic meteorologic anthropomorphic atherosclerotic epidemiologic stereoscopic bacteriologic antispasmodic stroboscopic spectroscopic submicroscopic electroscopic