The phrase "all opaque" is correct and usable in written English.
It can be used to describe something that is completely non-transparent or unclear, often in a metaphorical sense.
Example: "The instructions were all opaque, leaving us confused about how to proceed."
Alternatives: "entirely unclear" or "completely non-transparent".
It was all opaque, delightfully mysterious.
Generously season the flesh side of the sardine fillets, then lay them skin side down in the pan and cook for about two minutes, until the flesh is just about all opaque.
This is all opaque to you, the user, of course.
Martin Crimp, who adapted the version, and I agreed that he would confront all the opaque 19th-century references, either replacing them with equivalent, more familiar anecdotes or references, or removing them altogether.
So we could ignore criticism that was directed right at us and speculate instead about all those opaque symbols, those riddles, that seem to have stuck in your mind, too.
A bleached photographic film is a developed photographic film where all the opaque regions are transformed into transparent by another chemical processing.
Mr. Brill brings a lot of transparency to this all-too-opaque sector.
The National Archives, when it took over the museum in 2007, insisted that the museum close down what was by all accounts an opaque and perfunctory depiction of Watergate that Nixon's associates had originally installed with the former president's active involvement and approval.
That is a project of Freedom for All Americans, an opaque donor-led effort to support anti-discrimination work in the 31 states that have no protections.
It should flake easily and look opaque all the way to the bone.
(The fish is done when it is just about opaque all the way through, and offers no resistance to a thin-bladed knife).
