mute, tongueless, unspoken, wordless(adj)

expressed without speech

"a mute appeal"; "a silent curse"; "best grief is tongueless"- Emily Dickinson; "the words stopped at her lips unsounded"; "unspoken grief"; "choking exasperation and wordless shame"- Thomas Wolfe

unexpressed, unsaid, unstated, unuttered, unverbalized, unverbalised, unvoiced, unspoken(adj)

not made explicit

"the unexpressed terms of the agreement"; "things left unsaid"; "some kind of unspoken agreement"; "his action is clear but his reason remains unstated"

unspoken(adjective)ʌnˈspoʊ kən

understood without being spoken

an unspoken bond between the men

unspoken(Adjective)

Not spoken; not said.

unspoken(Adjective)

Not formally articulated or stated; implicit or understood.

The unspoken rule is to start a new pot of coffee when it is empty.