There are several synonyms for the phrase "put into circulation." One common synonym is "distribute," which refers to the act of spreading something out or delivering it to multiple locations or individuals. Another synonym is "release," which implies that something is being set free or made available to the public. "Introduce" is another synonym that suggests the act of presenting something new to others for the first time. Other possible synonyms for the phrase include "disburse," "issue," and "propagate." Overall, these synonyms all convey the idea of something being put out into the world for others to access or make use of.