Polykarp Leyser may refer to:

• Polykarp Leyser the Elder (1552 – 1610), German Lutheran theologian, superintendent in Braunschweig
• Polykarp Leyser II (1586 – 1633), German Lutheran theologian, superintendent in Leipzig
• Polykarp Leyser III (1656 – 1725), German Lutheran theologian, superintendent, chaplain and orientalist
• Polykarp Leyser IV (1690 – 1728), German Lutheran theologian, philosopher, physician, lawyer and historian

• Decadron-La
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• Decad (Sumerian texts)
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• Deca (Journalism Collective)
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• Decalogue Stone (disambiguation)
• Decalogue stones
• DE Cam
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