资料来源 : Webster's Revised Unabridged Dictionary (1913)

Immatureness \Im`ma*ture"ness\, n.
   The state or quality of being immature; immaturity. --Boyle.

资料来源 : WordNet®

immatureness
     n : not having reached maturity [syn: {immaturity}] [ant: {maturity}]