[f. LOP v.3 + -Y.] Of the sea: ‘Lumpy,’ ‘choppy’; cf. LOPPING ppl. a.3

1

1883.  Pall Mall Gaz., 17 May, 3/2. The Channel was somewhat loppy, as usual.

2

1891.  J. H. Pearce, Esther Pentreath, IV. ix. The sea was getting ‘loppy’ in the crowded little harbour.

3