入

rù
  1. to enter; to go into
  2. to join; to become a member of
  3. (bound form) to conform to (as in 入時 rùshí)
  4. abbr. for 入聲 rùshēng
  5. (on product packaging, after {number n} + {classifier}) containing (n pieces) (from Japanese 入 "iri")

CEDICT