is a specific kind of: reaction, response.

is a broader term that covers: accommodation reflex | Babinski, Babinski reflex, Babinski sign | belch, belching, burp, burping, eructation | blink, blinking, eye blink, nictation, nictitation, wink, winking | blush, flush | disgorgement, emesis, puking, regurgitation, vomit, vomiting | defecation reflex, rectal reflex | oscitance, oscitancy, yawn, yawning | electric shock, electrical shock, shock | breaking wind, fart, farting, flatus, wind | gulp, gulping | knee-jerk reflex, knee jerk, patellar reflex | light reflex, miosis, myosis, pupillary reflex | mydriasis | micturition reflex | gag reflex, pharyngeal reflex | goose bump, goose pimple, goose skin, goosebump, gooseflesh, horripilation, pilomotor reflex | plantar reflex | rooting reflex | jump, start, startle | myotactic reflex, stretch reflex | suckling reflex | shake, shiver, tremble | sneeze, sneezing, sternutation | hiccough, hiccup, singultus ... show more.

derivation: automatic, reflex, reflexive.