SOLUTION TO PRIZE CROSSWORD No 15,672:

ACROSS: 1 Ulterior. 5 Phlegm. 9 Mistaken. 10 Emboss. 12 Seep. 13 Balderdash. 15 Postoperative. 19 Opportunistic. 23 Unyielding. 25 Dada. 28 Dreary. 29 Ablution. 30 Modern. 31 Negation. DOWN: 1 Unmask. 2 Taste. 3 Roan. 4 Oregano. 6 Homer. 7 Egomaniac. 8 Mischief. 11 Idle. 14 Tsar. 15 Poppy seed. 16 Pin. 17 Anti. 18 Corundum. 20 Undo. 21 Ignoble. 22 Tannin. 24 Error. 26 Alibi. 27 Puma.