age spot       
noun [ C ] uk/ˈeɪdʒ ˌspɒt/ us/ˈeɪdʒ ˌspɑːt/
 老人斑,老年斑
a small, dark area that appears on the skin of older people
  His hair is now snow-white and his face mottled with age spots. 他的头发如雪般纯白,脸颊布满老年斑。 
 Sun protection helps prevent age spots. 防晒霜可以预防老年斑。 
 Synonym: liver spot
 - More examples
 - "They're freckles." - "They're age spots, Miriam."
 - Six decades later, age spots mark her hands.
 - I was hoping this book would give me a few laughs and some reflections on how to deal with sagging breasts, age spots and neck wattles.
 - Focusing on cosmetic concerns, such as wrinkles and age spots, instead of cancer might be the way to convince young people of the dangers of UV light.