The phrase "visible indicator" is grammatically correct and can be used in written English.
It refers to an object or sign that can be seen and is used to convey information or signal something. Example: "The stop sign was a visible indicator for drivers to come to a halt."
They're a visible indicator of how well, or how badly, a local economy is doing.
Curiously litter, a very visible indicator of cleanliness, is not considered at all.
It is the only visible indicator that she is suffering from leprosy, formally known as Hansen's disease.
Placing a C-level executive at the helm of corporate sustainability efforts is a highly visible indicator of commitment to responsible business.
Long lines on Election Day can be a visible indicator that polling place resources have been inadequately deployed to serve the needs of voters in a polling place.
But it was so dark outside that a halo of light from Reno, Nev., 35 miles away as the crow flies, beyond Cone Peak, was the most visible indicator of civilization.
However, increasing the amount and diversity of color, as well as visible indicators of 'human intent' for the landscape, increased preference levels, as indicated by rank coefficient analysis and multi-dimensional scaling (MDS).
For one thing, there are visible indicators that diplomatic and defense policy are bearing fruit.
Cardboard grannies are one of the most visible indicators of Hong Kong's struggle to support its rapidly ageing population.
Barrelle said none of these acts necessarily showed Monis was radicalised but "in aggregate they do lean towards visible indicators that a person is heading in that direction".
Fashion and jewelry are among the most visible indicators of what a society values, what it lacks and desires, mourns and celebrates.
