Prior to the recombination epoch, this soup, a plasma, was largely opaque to the electromagnetic radiation of photons.

The conventional greenhouse effect occurs because the atmosphere is largely transparent to solar radiation, but largely opaque to infrared.

These windows are largely opaque to hide tall buildings behind and to disguise the fact that the East wall is a wedge in plan.

However these prosecutions were the exceptions in a trade largely opaque to the authorities and an important part of the economy.

Though political developments inside North Korea remain largely opaque, this spurt of diplomatic activity must be considered encouraging.

It might be largely opaque to her sensors, but it would present little obstacle to her weapons.

"The market for prescription drugs has been largely opaque," Mr. Yocum said.

For instance, some kinds of glass, while transparent in the visual range, are largely opaque to ultraviolet light.

The affairs of Mundania are largely opaque to ordinary folk, and it was only twenty years later that we were to learn his fate there.

The selection criteria are largely opaque as no strictly enforced defined guidelines exist.