/roh"lok'/ ; for 3 also Naut. /rol"euhk, rul"-/ , n.
1. Archit. one of several concentric rings of masonry forming an arch.
2. a brick laid on edge, esp. as a header. Cf. soldier (def. 7).
3. Chiefly Brit. oarlock.
Also, rollock (for defs. 1, 2).
[ 1740-50; var. of OARLOCK; see ROW 2 ]