Silentious

Yet Will had very good qualities too: gentle, tractable, and, above all, grateful; silentious, even to a fault: he spoke, at any time, very little, but made it up emphatically with action;

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Can Bruce be other than Scotch? They are far more entertaining, I think, as well as informing, taken in the common run, than we silentious English; who, taken en masse, are tolerably dull.

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It [the love of learning] is there [in Oxford] so fitly housed […] that it might almost dream itself a type of what should always and everywhere be an emanation of the literature to which it shall return after its earthly avatar, and rest, a blessed ghost, between the leaves of some fortunate book on an unvisited shelf of a vast silentious and oblivious library.

Source: wiktionary

“[…] As I’m fond of informing some of my less educated but wealthy clients, ‘silence is often the answer’. Let’s say ten thousand pounds or guineas: could that buy a silentious disposition, sir?”

Source: wiktionary