What suffix would you use to indicate an abnormal condition?

The suffix that indicates an abnormal condition is -osis. This term is frequently used in medical terminology to describe a pathological state or a process that is abnormal, such as "leukocytosis" (an increased number of white blood cells) or "spondylosis" (a degenerative condition of the spine).

While other suffixes have their specific meanings, they do not universally convey an abnormal condition as -osis does. For instance, -itis is used to indicate inflammation (such as in "arthritis"), -pathy refers to disease or suffering (as in "neuropathy"), and -otomy denotes a surgical incision or cutting into something (as in "laparotomy"). Each of these serves a distinct role in medical terminology, but -osis is specifically associated with indicating various forms of abnormality.