The phrase "a sun umbrella" is correct and usable in written English.
It can be used to refer to an umbrella specifically designed to provide shade from the sun, often used at the beach or in outdoor settings.
Example: "We packed a sun umbrella for our day at the beach to protect ourselves from the harsh sunlight."
Alternatives: "beach umbrella" or "sunshade".
The day of the attack, he was sitting under a sun umbrella 200 yards south of the hotel in his trademark hat with four feathers.
— For Na Yeon Choi and Amy Yang, it was no big deal to cast aside their competitive instincts for the moment as they walked down the 15th fairway at the 67th United States Women's Open, sharing a sun umbrella.
Our youngish hosts, Tyler Clegg Sterck and his wife, Jeanne, threw in use of beach chairs and a sun umbrella and even two balloon-tire bicycles that could be ridden only outside Ocean Beach.
There are no facilities, so remember to bring drinking water, and perhaps a sun umbrella and suncream, as the few fig trees around the pools don't create much shade.
The best place to enjoy the lovely wines of San Felice would be sitting in the shade of the vine-covered arbor, or under a sun umbrella on the terrace beside the pool of this lovely Relais & Chateaux hotel.
Here's how it would go down: Pour baby oil over every inch of your body, head to the beach never spending a single minute under a sun umbrella, and fry your skin to a crisp.
There were some who had concerns about Danny, as the parade, with salsa dancers and other proud and excited Bronx Little Leaguers, made its way from 165th Street to the Bronx Courthouse. Louis Rivera, 40, a sun-umbrella salesman who lives on Laconia Avenue and was attending the parade "to see the kids and make a few bucks," admitted that if Danny was 14, he would be upset.
Where?" By late afternoon, scores of blue-shirted Murr campaign workers had set up their computer operation again on tables under a white sun umbrella inside the police lines and were busily checking the voters in.
They backed up, still facing the sun umbrella, and after a while the boy took his fingers out of his mouth and gave her a hesitant thumbs-up.
According to her calculations, they were a little less than fifty metres away from the sun umbrella.
The instructions for it were long, and she didn't want the man to think that he had the power to make her move faster, so she shooed him away without a word of promise, and sat on the plastic chair under the sun umbrella to read.
