Wanly is the adverb from wan. It describes doing something in a pale, weak, tired way — with no strength or brightness behind it. In real use it lives with a very small number of verbs, and by far the commonest is smile. 'She smiled wanly' means she gave a small, weak smile with no happiness in it — the smile of someone who is sad, ill, or exhausted but trying to be polite. If you learn only one phrase, learn that one. You will also meet 'he nodded wanly', 'she looked at me wanly', and — for light — 'a lamp glowed wanly in the window', meaning it gave weak, pale light. This is a written word. It belongs to novels and stories, where a writer wants to show a character's state without saying 'she was very tired and sad'. In conversation nobody says it. If you want the spoken version, say 'she smiled, but it was a weak smile'. It is worth knowing all the same, because reading English novels means meeting wanly regularly — and once you see it, you know at once that the character is running on empty.

（微笑、點頭等）虛弱無力地、有氣無力地；（燈光）微弱慘淡地。最常見的搭配是 smile wanly「勉強擠出一個笑」。屬書面語，口語不用。