Particle
Usually written in kana
1.  only;  merely;  nothing but;  no more than
2.  approximately;  about
3.  just (finished, etc.)
after the -ta form of a verb
4.  as if to;  (as though) about to
after an attributive form or auxiliary verb ぬ(ん), also often …とばかり(に)
5.  indicates emphasis
often …とばかり(に)
6.  always;  constantly