Japanese for electricity (also denki). Here is the Kanji:

          ############
               #
      ####################
      #        #         #
      #  ###   #   ###   #
      #        #         #
      #  ###   #   ###   #
               #
         #############
         #     #     #  
         #############
         #     #     #
         #############   #
               #        ##
               ###########

The top half of this kana represents rain (ame) as rain falling from a cloud. The bottom half is the prototype of lightning. This character can still occasionally mean lightining, but is usually used nowadays to refer to electricity.

Den (?), n. [AS. denn; perh. akin to G. tenne floor, thrashing floor, and to AS. denu valley.]

1.

A small cavern or hollow place in the side of a hill, or among rocks; esp., a cave used by a wild beast for shelter or concealment; as, a lion's den; a den of robbers.

2.

A squalid place of resort; a wretched dwelling place; a haunt; as, a den of vice.

Addison.

3.

Any snug or close retreat where one goes to be alone.

4. [AS. denu.]

A narrow glen; a ravine; a dell.

Shak.

© Webster 1913.

Den, v. i.

To live in, or as in, a den.

The sluggish salvages that den below. G. Fletcher.

© Webster 1913.