The Collaborative International Dictionary of English v.0.48:

Chicle \Chic"le\, n., Chicle gum \Chicle gum\ [Amer. Sp.
   chicle.]
   A gumlike substance obtained from the bully tree (Mimusops
   globosa) and sometimes also from the naseberry or sapodilla
   (Sapota zapotilla). It is more plastic than caoutchouc and
   more elastic than gutta-percha, as an adulterant of which it
   is used in England. It is used largely in the United States
   in making chewing gum.
   [Webster 1913 Suppl.]