abbr. 
（Identification Friend or Foe）
（Identification Friend or Foe）iff
n.
且仅iff
abbr. if and only if且仅…时,在而且只有在…时用户正在搜索
drill instructor, drill rig, drill rod, drill steel, drillability, drillable, drill-and-thinner, drillcat, driller, drillers,
相似单词
IFCS, IFDF, ife, IFEMS, ifenprodil, IFF, iffish, iffy, IFG, IFI,