"Loosens up" is a common expression used to indicate a state of relaxation or becoming more laid back. However, there are several synonyms that can be used to describe a similar state of being. For instance, the phrase "letting go" implies the release of tension or worries. Likewise, the word "unwinding" suggests a similar sense of relaxation or decompression. Other alternatives to "loosening up" include "chilling out," "mellowing out," and "de-stressing." Regardless of which synonym is used, the overarching meaning remains the same: to find a sense of ease and calm.