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