Un ostentatiousness is a word that describes someone or something that avoids being showy or flashy. There are several synonyms for this word, including modesty, simplicity, unpretentiousness, understatedness, and plainness. Modesty is a humble quality that avoids drawing attention to oneself, while simplicity implies a lack of complexity and adornment. Unpretentiousness refers to a lack of affectedness or artificiality, while understatedness suggests a subtle or restrained quality. Finally, plainness describes something that is straightforward and unadorned, without any embellishments or ornaments. All of these words signify a desire to be unassuming and avoid any show of wealth, power or prestige.