2  "... they shall be as white as ___" (Isa 1:18) (4)

 6  "... ___ nisi bonum" (3)

 8  "Let's ___" (child's favorite) (7)

11 "... silk purse out of a sow's ___" (3)

12 Authorize (7)

13 "The ___ With No Beer" (3)

15 Area (6)

16 At the end of one's rope (9)

18 "Cat on a Hot ___ Roof" (3)

 3  !(a || b) (to programmers) (3)

 4  "Seance on a ___ Afternoon" (3)

 5  Free. (11)

 7  British transport (5)

 8  "The Money ___" (Hanks/Long classic) (3)

 9  Adjective for snowboarding (7)

10 Certain to happen (8)

13 A mouse may move across one (3)

14 "But the ___ won't seem to let me" ("9 to 5" line) (4)

17 "Ceiling" room cooler (3)