High-definition medicine is emerging across all medical disciplines, but it is nonetheless important to recall the appropriate use of official definitions of illness, disease, sickness, co- and multimorbidity, as well as terms such as geriatric syndromes and polypharmacy. These classical definitions are coming up against precision medicine, which is based not only on genetic risks, but on a range of personalized parameters (nucleotides, epigenomics, cellular mosaicism, immunome etc). In this rapidly changing context, geriatric medicine appears very similar to so-called “P4 medicine” (predictive, preventive, personalized and participatory), in which the disease concept is increasingly being replaced by a functional approach to aging and the functional consequences of any clinical disorders. © 2020, Asian Association for Frailty and Sarcopenia and Taiwan Association for Integrated Care.