"silent assent" is a correct and usable phrase in written English.
It refers to the act of agreeing or consenting without speaking or showing any outward signs of approval. Here's an example of how it can be used in a sentence: "Despite not saying a word, the audience's silent assent to the speaker's message was evident through their nodding heads and attentive expressions."
He has given at least silent assent to full-on paranoia and racism among his supporters.
Both men nodded in silent assent when asked if the end of the partnership felt like a personal loss.
Although technically a minority government the two parties commanded exactly half the seats in parliament its creation was given silent assent by the nationalist Ataka party, which abstained from the vote that approved it.
In fact, both rights activists and legal experts say, the system for dealing with dissidents and other troublemakers is geared toward allowing local leaders to ignore the law, with Beijing's sometimes silent assent.
When we don't speak up, we contribute to silent assent.
Even giving silent assent or endorsement to acts of violence from far away has karmic consequences for the soul.
So, too, in the early days, the 'government, by its silent acquiescence, assented to the general occupation of the public lands for mining.' Atchison v. Peterson, 20 Wall.
Stay silent, and assent to the potential victimization of hundreds of thousands of blameless young immigrants, Americans in all but the strictest legal sense, who hold such promise.
Mr. Comey's comparison of the president's operating style to the Mafia — "The silent circle of assent.
For example, in a discussion of a White House meeting with Trump and then chief of staff Reince Priebus in February 2017, Comey says that "because he never stops talking", Trump "pulls all those present into a silent circle of assent".
