There are many synonyms for the phrase "holding together" that can be used to describe situations where things or people are kept in a cohesive unit. Some possible alternatives include "united," "bound," "connected," "cohesive," "integrated," "interwoven," "linked," "knit together," "unified," "cooperating," "joined," "solid," "intact," "unbroken," "combining," "fusing," and "maintaining a whole." Depending on the context, different synonyms might be more appropriate. For example, "cohesion" might imply a more abstract or collective sense of "holding together," while "solid" could refer to a more tangible or physical form of unity.