Having a young, healthy, clean-looking face — the look of someone who sleeps well, is often outdoors, and has not been worn down by life yet. It is a warm, friendly word, and it is almost always about young people: a fresh-faced student, a fresh-faced group of new soldiers. Because of that, it carries a second layer of meaning that dictionaries sometimes miss: fresh-faced people look INEXPERIENCED. When a newspaper calls a new politician fresh-faced, it is partly saying 'he looks young and healthy' and partly saying 'he has not done this before'. Depending on the writer, that can sound hopeful or slightly doubtful. You can say it of an older person too, but then it means 'looking younger and healthier than the years would suggest', and usually comes with something like 'still' — 'still fresh-faced at fifty'. Note it describes the whole impression a face gives, not one feature; you would not say a fresh-faced nose.