salt
鹽 centers on salt as a substance, especially in its traditional form as a mineral or seasoning.
鹽 is the traditional form of 塩. It combines 鹵 (salt) with 監 (to oversee), suggesting the supervision of salt production. The modern simplified form 塩 replaces the complex upper part with 土.
The bottom 皿 is a dish, and the upper part 鹵 looks like a container with salt crystals. Picture a dish filled with salt from a traditional salt bag.
For エン, imagine an English salt shaker labeled 'EN' (as in 'English salt') sitting on the dish: EN -> エン.