noun
plasterer
A tradesperson who applies plaster, mortar, or stucco to walls and ceilings. The reading しゃかん is less common.
彼は腕のいい左官だ。
He is a skilled plasterer.
左官の仕事は壁を塗ることです。
A plasterer's job is to plaster walls.
塗装工 is a painter (applying paint), while 左官 specifically works with plaster or mortar.
The term 左官 is said to derive from the official title 左官 (sakan) in the ancient Ritsuryō system, but the exact connection to the modern trade is uncertain.