A coffin is a container used to hold a deceased person's body.
Tips
usage
棺 alone means coffin but is often used in compounds: 棺材 (the more common word for coffin) and 棺椁 (inner and outer coffins used for nobles in ancient burials). 棺 is the inner coffin; 椁 is the outer one.
木 (wood) anchors the meaning: a 棺 is a wooden coffin. Traditional Chinese funerary practice prized thick-board cypress and pine coffins, and the wood radical groups it with 椁 (outer coffin), 板 (plank) and other carpentry words.
官 supplies the sound, unchanged. A faint semantic resonance lingers, coffins, like official seats, are formal vessels housing a body. The same phonetic drives 管 (tube / manage), 馆 (hall), 莞 (rush plant).