eaves
檐 centers on the projecting edge of a roof: the eaves that overhang a building to shed water and provide shade.
檐 combines 木 (wood/tree) with 詹, which likely contributes the sound. The character refers to wooden eaves, consistent with the wood radical.
The left side 木 suggests wood, and the right side 詹 looks like a roof with a protruding edge. Picture wooden beams extending out from under a roof to form the eaves.
For エン, imagine the eaves ending in a graceful curve: end -> エン, and the wooden eaves mark the end of the roof.