This week, I started the DT cryptic with some confidence because I could do quite a lot of the clues, but it turns out to be by the clever setter, some of whose clues are way beyond me, so this morning I have googled quite a few and, no, I wouldn't have got them.
One of the across clues is: Order 51 signs (5)
I could get O and LI for 51 but the answer appears to be OBELI. I googled definition and it offered 'obelisk' butcould someone please tell me what this word means and whether it is a good clue or not?!