pewh₂-
“to purify, to cleanse”purify, clean, clear
Root for purifying, yielding Latin purus (pure), putare (to prune/think), English pure.
Discussion
The PIE root *pewh₂- (to purify, to cleanse, to make bright) produced the vocabulary of ritual and physical purification across the western branches — words for cleaning, cutting, and making pure that connect the washbasin to the altar.
Latin pūrus (pure, clean, uncontaminated) continues the root and generated one of English's most important moral and scientific word families: pure, purity, purify, purge (pūrgāre, "to make pure" — to cleanse by removing impurities), and Puritan (one who seeks religious purity). The word expurgate (to purge a text of offensive material) and the chemical term pūrum (a purified substance) extend the family into editorial and laboratory vocabulary.
Latin putāre (to prune, to cleanse by cutting — connected to this root through the concept of purifying by removal) may be related, linking the purification root to the compute/dispute/reputation family through the shared image of cutting away what is unwanted.
Greek pŷr (πῦρ, "fire") is sometimes connected to this root through the concept of purification by fire — though most scholars derive pŷr from *péh₂wr̥ (the fire root) instead. The connection between fire and purity is cultural rather than etymological: fire purifies by burning away impurities, and the Latin lustrum (a purification ceremony involving fire) preserves this ritual logic.
Sanskrit pūtá- (purified, clean) and the related punā́ti ("he purifies") confirm the Indo-Iranian reflex. The Vedic concept of ritual purity — essential for performing sacrifices — deploys this root at the centre of religious practice.
The root's survival in both practical (cleaning, pruning) and sacred (ritual purification, moral purity) registers shows that the PIE speakers did not separate physical and spiritual cleanliness — to purify was a single act with both material and numinous consequences.
Notes
Pokorny 827. English pure, purge, Puritan, compute, dispute, amputate.