The Collaborative International Dictionary of English v.0.48:

maltese cross \maltese cross\ n. (Bot.)
   A Eurasian garden perennial (Lychins chalcedonica) having
   scarlet flowers in dense terminal heads.

   Syn: scarlet lychnis, Lychins chalcedonica.
        [WordNet 1.5]

   2. A cross with triangular or arrow-shaped arms and the
      points toward the center. See illustration under cross.
      [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Maltese \Mal*tese"\ (m[add]l*t[=e]s" or m[add]l*t[=e]z"), prop.
   a.
   Of or pertaining to Malta or to its inhabitants. -- n. sing.
   & pl. A native or inhabitant of Malta; the people of Malta.
   [1913 Webster]

   Maltese cross. See Illust. 5, of Cross.

   Maltese dog (Zool.), a breed of small terriers, having long
      silky white hair. The breed originated in Malta.
      [1913 Webster]

WordNet (r) 3.0 (2006):

maltese cross
    n 1: Eurasian garden perennial having scarlet flowers in dense
         terminal heads [syn: scarlet lychnis, maltese cross,
         Lychins chalcedonica]
    2: a cross with triangular or arrow-shaped arms and the points
       toward the center