Definitions of elliptical:

• adjective:   containing or characterized by ellipsis

  Example: "The clause of comparison is often elliptical- G.O.Curme"

• adjective:   characterized by extreme economy of expression or omission of superfluous elements

  Example: "The explanation was concise, even elliptical to the verge of obscurity- H.O.Taylor"

• adjective:   rounded like an egg