The phrase "kept hand" implies a sense of control or ownership over something. For antonyms of this phrase, one might consider "let go", "released", or "surrendered". These words suggest a willingness to relinquish control or ownership and allow something to exist or move freely. Other antonyms could include "lost", indicating a lack of control, or "misplaced", implying a sense of disorganization or forgetfulness. In contrast, synonyms for "kept hand" might include "held onto", "maintained", or "possessed". Ultimately, the choice of antonym would depend on the context in which the phrase is used and the meaning being conveyed.