1: One who gets up part of stairway (5)
5: Settler rearranged alphabet components (7)
9: Allow meathead into mine opening (5)
10: Before long 1000 French to be having Sunday fowl (7)
12: A friend starting to make word from letters (7)
13: Illegally hunted for a flower for a revolutionary dunderhead (7)
14: Is this a bird from Australia? (4-5)
15: Measure of beverage with even fewer calories? (5)
16: Spring water coming up natural, simple, and fresh (5)
18: Delilah, practically bare, cuts hair! (9)
20: Place to grow fruit trees, or a leafy veggie (7)
21: Kind of sign alphabet linked Italian leader with Fascist (3-4)
22: The day ends with an unpleasant ancestral line (7)
24: Confer higher rank upon former adversary's first lieutenant (5)
25: Do over eco-law lacking initiative (2-5)