捺印 （ナツイン） affixing a seal (to), putting one's seal (on)

押捺 （オウナツ） stamping, impressing, affixing a seal

指紋押捺 （シモンオウナツ） fingerprinting

押す （おす） to push, to press, to apply pressure from above, to press down, to stamp (i.e. a passport), to apply a seal, to affix (e.g. gold leaf), to press (someone for something), to urge, to compel, to influence, to overwhelm, to overpower, to repress, to push (events along), to advance (a plan), to do in spite of ..., to do even though ..., to force, to make sure, to be pressed for time, to advance troops, to attack, (of light) to be diffused across an entire surface