Definitions of elfin:

• adjective:   small and delicate

  Example: "She was an elfin creature--graceful and delicate"

• adjective:   suggestive of an elf in strangeness and otherworldliness

  Example: "Thunderbolts quivered with elfin flares of heat lightning"

• adjective:   usually good-naturedly mischievous

  Example: "Perpetrated a practical joke with elfin delight"

• adjective:   relating to or made or done by or as if by an elf

  Example: "Elfin bells"