From Longman Dictionary of Contemporary Englishsunspotsun‧spot /ˈsʌnspɒt $ -spɑːt/ noun [countable] technicalHA a small dark area on the sun’s surface
Examples from the Corpus
sunspot• Scientists are concerned that a special event, such as a sunspot or supernova might occur during this long period of communications blackout.• They say that the concentrated magnetic fields in sunspots spread out all over the sun somewhat after the maximum of solar activity.• They are probably produced by variations in sunspot activity.• A year later he published his three letters on sunspots.• Then he saw sunspots and described their variations.• In one such list the Jesuit astronomer Christopher Scheiner is included for his discovery of the sunspots.• It also shows a clear relationship with sunspot activity; by and large there are fewer sunspots when the Sun is bigger. 