/ˈsæŋktɪfaɪ/
[verb] To make something holy or sacred, or to officially approve something and give it a special, respected status. It can also mean to free someone from sin or to make an action seem morally acceptable.
The Latin root 'sanctus' comes from a verb meaning 'to make an agreement with the gods' — turning a legal act into a divine one.
The story of 'sanctify' begins in ancient Rome, with the Latin verb 'sancire', meaning to make sacred, to decree, or to ratify something by a religious act. This was a deeply practical word in Roman life — laws, treaties, and boundaries were 'sanctioned' through rituals that called the gods as witnesses. From 'sancire' came the past participle 'sanctus', meaning holy or consecrated, which became one of the most powerful words in the Latin language.
From 'sanctus', Latin formed the verb 'sanctificare', combining 'sanctus' (holy) with 'facere' (to make). The literal meaning is therefore beautifully direct: 'to make holy'. This compound verb passed into Late Latin and was widely used in Christian religious texts, particularly in the Latin Bible known as the Vulgate, where it appeared in prayers, blessings, and descriptions of God's power to purify the soul.
The word reached English through Old French, where 'sanctificare' became 'sanctifier', following the natural softening and shortening that Old French applied to Latin verbs. By the late 14th century, English writers and clergy — deeply familiar with both French and Latin through the Church — adopted the word as 'sanctify', giving it a recognisably English shape while keeping its sacred meaning almost perfectly intact.
In its early English use, 'sanctify' was almost entirely a religious word. It described the act by which God, a priest, or a ceremony made something or someone spiritually pure and set apart for divine purpose. You might sanctify a church, a marriage, the Sabbath day, or a person's soul. The word carried enormous weight — it meant not just cleaning something, but lifting it into a higher, untouchable category of existence.
Over time, 'sanctify' developed a secondary, more worldly meaning: to give something moral authority or social approval. By the 17th and 18th centuries, writers began using it to describe how tradition, law, or public opinion could 'sanctify' a custom — even an unjust one. This gave the word a slightly ironic edge that it still carries today. When someone says a practice is 'sanctified by tradition', they may be praising it or quietly questioning whether tradition alone is enough reason to accept it.
The family of words that 'sanctify' belongs to is enormous and deeply familiar. The root 'sanctus' gave English 'saint' — through Old French 'saint' from Latin 'sanctus' — and also 'sanctuary', 'sanction', 'sanctimonious', and 'sacred' itself. Even the name 'San Francisco' carries the same root, preserving in a California city name the very Latin word that Roman priests once used to call down the blessing of the gods.