Snellius

Snellius may refer to:

• Rudolph Snellius (1546–1613), Dutch linguist and mathematician at the Universities of Marburg and Leiden
• Willebrord Snellius (1580–1626), Dutch astronomer and mathematician, most famous for the law of refraction now known as Snell's law
• Snellius (crater), a lunar crater located near the southeast limb of the Moon
• Vallis Snellius, a linear valley on the near side of the Moon