oar, tower
櫓 centers on a tall wooden structure: a tower or a long oar used to propel a boat. Both senses share the idea of a large, upright wooden implement.
櫓 combines 木 (wood) with 魯, which likely contributes the sound ロ. The character originally referred to a wooden tower or a large oar, both made of wood.
The left side is wood 木, and the right side 魯 looks like a fish 魚 over a fire 灬. Picture a tall wooden tower by the water where fish are grilled, or a long wooden oar shaped like a fish skeleton.
For ロ, imagine a row of wooden towers along a river: row -> ロ, and each tower is made of wood like the left side 木.
turret; watchtower
Japanese scull (oar attached to the rear of the boat by a traditional peg-in-hole oarlock)
drums which announce the opening of a stage performance or commencement of bouts; the sound produced by such drums
inner thigh throw
fulcrum peg (fitted into the cavity in an oar as part of a traditional oarlock)
sculls and paddles
fulcrum peg (fitted into the cavity in an oar as part of a traditional oarlock)
fire lookout; watchtower
watchtower; observation tower; lookout
observation tower; scout tower