The phrase "trademark smile" refers to a smile that is unique and recognizable to a particular person. It is often used to describe someone's distinctive or signature smile. Full definition
Chanel Iman flashed us her megawatt trademark smile whilst wearing the same Marc Jacobs Resort 2010 dress we've seen on Anne Hathaway. (redcarpet-fashionawards.com)
One reason Buddhists are accepted more often than they are feared in the United States is that when we think of Buddhism we think of the Dalai Lama and his trademark smile. (religion.blogs.cnn.com)
Applause greeted the surprise from those who saw it as the president lay down, wearing his trademark smile and dark spectacles, in a display that lasted about 40 seconds. (ghanapoliticsonline.com)