Webster's English Dictionary

Enter the word to look up:

tetrad

tet.rad \'te-.trad\ \te-'trad-ik\ n [Gk tetrad-, tetras, fr. tetra-] : a 
   group or arrangement of four : as  : a tetravalent element, atom, or 
   radical  : a group of four cells arranged usu. in the form of a tetrahedron 
   and pr oduced by the successive divisions of a mother cell : an arrangement 
   of chromosomes by fours in the first meiotic prophase du e to precocious 
   longitudinal splitting of paired chromosomes - te.trad.ic aj