Grinner is the word used to refer to a person who is always smiling or grinning. However, there are many other synonyms for this expression. Some of the commonly used terms include smiler, laugher, giggler, cackler, chuckler, jester and prankster, among others. Each of these synonyms evokes a different type of expression, and they can be used to describe specific types of people who like to smile or laugh. A smiler might be a shy person, while a cackler could be someone with a loud and infectious laugh. Regardless of the specific term used, all of these synonyms convey a sense of joy and lightheartedness, making them useful expressions for writing and speaking.