The phrase "tack together" refers to the act of assembling or connecting various elements in a rough or temporary manner. Some antonyms for "tack together" would include disassemble, disconnect, disjoin, dismantle, or detach. These are all verbs that convey an opposite action, indicating the act of separating or breaking apart something that was previously joined together. Other possible antonyms for "tack together" could include words such as deconstruct, scatter, fragment, disrupt, or disperse, which indicate a more forceful or complete separation of elements. Overall, antonyms for "tack together" suggest a different approach to creating unity or coherence, one that emphasizes structure, permanence, or thoughtfulness.