The term "lost cool" refers to a state of agitation or loss of composure. There are several synonyms that can be used to describe this state of mind, including agitated, flustered, frenzied, panicked, rattled, uneasy, and unsettled. Other synonyms that could be used include discomposed, distressed, perturbed, ruffled, and unnerved. When someone has lost their cool, they may exhibit behaviors such as yelling, screaming, or becoming physically agitated. It is important to remember that everyone experiences moments of anger or frustration, and it is important to seek help if these moments become overwhelming or affect daily life.