Inseparable

a.	1.
	1.	Not separable; incapable of being separated or disjoined. The history of every language is inseparable from that of the people by whom it is spoken. - Mure. Liberty and union, now and forever, one and inseparable. - D. Webster.
	2.	(Gram.) Invariably attached to some word, stem, or root; as, the inseparable particle un-.

Adj.

1.

inseparable - not capable of being separated; "inseparable pieces of rock"

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