"Absentment" is a relatively uncommon word used to describe the state of being absent or away. However, there are several synonyms that can effectively convey the same meaning. For instance, the term "absence" aptly captures the concept of not being present. Similarly, "nonattendance" denotes the act of not attending or being absent. Another synonymous word is "nonappearance", which emphasizes the absence of someone or something. Additionally, "unavailability" conveys the idea of not being present or accessible. These synonyms effectively communicate the notion of being away or not being present in various contexts, allowing for more diverse and expressive language use.