Inseparable

1. (a.) Incapable of being separated or disjoined.

2. (a.) Invariably attached to some word, stem, or root; as, the inseparable particle un-.

Thesaurus Entries

bound up in, bound up with, close, coherent, cohesive, familiar, hand and glove, hand-in-hand, impartible, inalienable, indiscerptible, indissoluble, indissolvable, indivisible, infrangible, infusible, insoluble, intimate, near, thick, thick as thieves, undividable, unified