tray for carrying sacrificial meat
梡 centers on a wooden tray used specifically for carrying sacrificial meat in ritual contexts.
梡 combines 木 (wood) with 完, which likely contributes the sound. The character denotes a wooden ritual tray.
The left side 木 (wood) and right side 完 (complete) suggest a wooden tray that completes a sacrificial ceremony by holding the meat.
For カン, imagine a can-shaped wooden tray holding the sacrificial meat: can -> カン.