The word 作呕 (zuò'ǒu), meaning "to feel nauseated" or "to be sickening/disgusting", is a compound formed through semantic combination. The first character 作 means "to do" or "to make", while the second character 呕 means "to vomit". Together, they create a verb-object structure that literally reads as "to make vomiting" or "to induce retching". This formation vividly metaphorizes a strong physical reaction of nausea to convey intense psychological or aesthetic disgust, transitioning from a direct description of a physical reflex to a common idiomatic expression for revulsion.