The term "prediagnosis" refers to symptoms or signs that indicate the possible onset of a medical condition or disease. There are several alternative phrases which can be used to convey this concept. "Pre-symptomatic" describes a period before symptoms manifest themselves. "Prodromal" suggests the early, mild stages of an illness, before it has fully developed. "Preclinical" implies a stage of illness before it can be detected by normal diagnostic testing. "Pre-illness" can be used to describe a state in which disease has not yet been clinically diagnosed, but there are indications that it may be present. These synonyms can help to convey a nuanced understanding of the time before a formal diagnosis is given.