fulcrum peg; oarlock pin
A wooden peg fitted into a cavity in an oar, used as part of a traditional Japanese oarlock (入れ子). This is a specialized nautical term.
See also: 入れ子
On a traditional Japanese boat, you insert the fulcrum peg into the oarlock and row.
Standard kanji spelling for the fulcrum peg in a traditional oarlock.
Variant kanji spelling using 艪 (oar) instead of 櫓 (scull).
Compound of 櫓 (ro, 'scull') and 杭 (kui, 'stake, peg'). The reading ろぐい is a standard rendaku form.