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