Denshi Jisho — Online Japanese dictionary

押す おす 1: to push; to press;
2: to apply pressure from above; to press down;
3: to stamp (i.e. a passport); to apply a seal
Common word, Godan verb with su ending, Transitive verb 
押すな押すな おすなおすな crowded (e.g. with people); overflowing
No-adjective 

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