Diminutive of Teresa, from Greek 'therizein' meaning to harvest, or from the island Thera.
Teri is a variant spelling of Terry or Terri, themselves diminutive forms of the name Theresa, which derives from the Greek Theresia — a name whose ultimate etymology remains pleasingly debated. One tradition connects it to the Greek island of Thera (modern Santorini), suggesting a geographical origin; another links it to the Greek verb therízō, meaning to harvest or to reap, lending the name an agrarian, seasonal quality. Whatever its ultimate roots, Theresa entered Christian history primarily through Saint Teresa of Ávila (1515–1582), the Spanish mystic, reformer, and Doctor of the Church whose writings on contemplative prayer remain foundational in Catholic spirituality.
The shortened form Teri gained particular traction in mid-twentieth-century America, when breezy, phonetically spelled nicknames became fashionable as standalone given names — Terry, Sherri, Patti, Dani. The -i ending replaced the traditional -y to give the name a jaunty written femininity. Teri Garr, the American actress beloved for her comic timing in films like Tootsie and Young Frankenstein, is among the most recognizable bearers of this exact spelling, lending it a warm Hollywood glow.
Today Teri feels like a time capsule of mid-century American naming fashion — cheerful, unpretentious, and instantly evocative of a particular cultural moment. It has the nostalgic charm of a drive-in diner: it may not be the most fashionable choice right now, but its simplicity and warmth ensure it ages well on real people who carry it through life.