two dimensions; fictional world of anime, manga, video games, etc.
after-party; second party (of the night); second meeting
derivative work (usu. unauthorized and produced by fans, e.g. dōjinshi, fanfiction)
two-dimensional complex; people more interested in two-dimensional (i.e. anime or manga) girls than real people
secondary cooling water (esp. in a pressurized water reactor)
secondary electron multiplier
being victimized after reporting sexual or other harassment