Otiosities are defined as insignificant or useless things. Antonyms for this term could be useful, valuable, essential or necessary. The opposite of otiosities would be significant or imperative items that hold importance or contribute to a collective purpose. Synonyms for otiosities include frivolities, trivialities, and superfluities. On the other hand, antonyms emphasize the relevance of the object or concept in question, whereas synonyms highlight similarities in meaning. By utilizing antonyms, one is able to convey the positive characteristics of a particular idea or thing, and emphasize its value in a given context.