Flitters, a relatively uncommon word, means to move quickly and lightly from one place to another or to behave in an erratic or fickle manner. There are several synonyms to use in place of flitters that can add variety to your writing. For example, the word "flits" has a similar meaning and can be used interchangeably. Additionally, the words "flickers," "darts," and "skips" can convey the same sense of quick and playful movement. If describing an unsteady behavior, try using "wavers," "vacillates," or "wavering." Whatever synonym you choose, remember to use it correctly in context to avoid confusion or incorrect categorization of your writing.