1. Indicating a lack of maturity
   "infantile behaviour"
   - childish 
2. Of or relating to infants or infancy
   "infantile paralysis" 
3. Being or befitting or characteristic of an infant
   "infantile games"

See also: immature, infancy, young

• unblock
• unbloody
• unblushing
• unblushingly
• unbodied
• unbolt
• unbolted
• unbooked
• unbordered
• unborn
• unbosom
• unbound
• unbounded
• unbounded interval
• unboundedness
• unbowed
• unbox
• unbrace
• unbraced
• unbraid
• unbrainwashed
• unbranched
• unbranching
• unbranded
• unbreakable