Blew off steam is an idiom that refers to the act of releasing pent-up emotions or frustrations. There are several synonyms that one could use instead of this phrase to convey a similar meaning. For example, some people might say that they vented their frustrations, blew a fuse, or had a meltdown. Others might say that they expressed their feelings or simply let it out. Regardless of the specific term used, the common theme is that individuals are finding a way to release their emotions in a constructive manner. By doing so, they are able to reduce their stress levels and feel more in control of their thoughts and actions.