The word "instillation" refers to the process of introducing something gradually and in small quantities, and it can be used in various contexts such as medicine, art, and technology. There are several synonyms for the word "instillation," and each one conveys a slightly different meaning or application. Some of the synonyms for "instillation" include infusion, injection, implantation, introduction, insertion, installation, and instilling. Infusion refers to the introduction of a substance into a solution, injection refers to the introduction of a fluid into the body, implantation refers to the insertion of an object into the body, and the other synonyms relate to the general idea of gradual introduction or installation.