Ivory is similar to off-white. White symbolically represents purity, but because ivory isn't pure white, it represents pride or piety...and a tower is a place of high authority and protection...I don't know if this is the origin, but it does define the term clearly.

The term was first used in Song of Solomon 7:4, but its meaning is different. Its current meaning seems to be from French tour d'ivoire, in an 1837 poem by Charles Augustin Sainte-Beuve, where it is used to describe the poetical attitude of Alfred de Vigny as contrasted with the more socially engaged Victor Hugo. The first known written use in English is H. L. Bergson's Laughter (1911) by Frederick Rothwell and Cloudesley Shovell Henry Brereton. http://en.wiktionary.org/wiki/ivory_tower The first mention of ivory towers is in the Bible, Song of Solomon 7:4 (King James Version): Thy neck is as a tower of ivory; thine eyes like the fishpools in Heshbon, by the gate of Bathrabbim: thy nose is as the tower of Lebanon which looketh toward Damascus. That biblical allusion is to the notion of ivory towers as symbols of virginal purity. The contemporary figurative meaning is of a place of unworldly isolation. This may be in allusion to the famous Hawksmoor Towers of Oxford University's All Souls' College, which are ivory in colour (or at least, they were when they were built in 1716). The relative lateness of the first uses of the phrase (below) tend to argue against that derivation. There are citations of the term in French in the 19th century but the earliest work in English that specifically refers to the current meaning of the phrase is a collaborative work of Frederick Rothwell and the splendidly named Cloudesley Shovell Henry Brereton -H. L. Bergson's Laughter, 1911: "Each member [of society] must be ever attentive to his social surroundings - he must avoid shutting himself up in his own peculiar character as a philosopher in his ivory tower." http://www.phrases.org.uk/meanings/210800.html The origin is the Bible, specifically Chapter 7, Verse 4 of the Song of Solomon, in which Solomon is extolling the beauty of his beloved: “Thy neck is as a tower of ivory; thine eyes like the fishpools in Heshbon, by the gate of Bathrabbim: thy nose is as the tower of Lebanon which looketh toward Damascus”. Not quite the thing today — few young women would want their eyes compared with fishponds (or their noses with towers) — but it struck a chord with Charles-Augustin Saint-Beuve. He was a French literary critic and poet of the early part of the nineteenth century. He wrote a poem in October 1837 called Pensés d’Août (Thoughts of August) in which he refers to two fellow poets, Victor Hugo and Alfred de Vigny. I’ll spare you the whole thing, but in English the third stanza goes roughly like this: Hugo, strong partisan ... fought in armour, And held high his banner in the middle of the tumult; He still holds it; and Vigny, more discreet, As if in his ivory tower, retired before noon. He was suggesting that Alfred de Vigny was aloof from the cares and practicalities of daily life. That’s how we use the idiom today: someone living in an ivory tower is — by accident or design — sheltered from the realities of existence, out of touch with the real world. Saint-Beuve’s allusion was picked up by Henry James, who used it as the title of a book in 1916. It became very popular and was used in the next two decades by H G Wells, Hart Crane, Aldous Huxley, Ezra Pound and others, ensuring it a lasting place in the language. But why ivory? I’m far from sure that I’ve got to the bottom of Saint-Beuve’s allusion. The Song of Solomon was obviously referring to the whiteness of ivory. That’s the colour also of purity and chastity, perhaps suggesting an innocence and lack of exposure to worldly cares. Ivory has also been a symbol for hardness: unbreakable and incorruptible. Saint-Beuve may also have had in mind a famous sentence from the Greek epic The Odyssey: “Those that come through the gate of ivory are fatuous, but those from the gate of horn mean something to those that see them”. So ivory may also have suggested foolishness or naivety. http://www.worldwidewords.org/qa/qa-ivo1.htm

I'm not exactly sure which one you're referring to however, I've been told several times that I have a "ivory tower" :-)

In corporate lingo "Ivory Tower" refers to the special interests of a particular indivual who seems to look out for his own interests as opposed to contributing to the interests of all concerned. i.e., he's not a team player. "That guy's protecting his own little IVORY TOWER".

Man! What a *great* "straight line", no? But, alas, inappropriate for AB! ;-)

I am pleased to see that VS Prasad did some research. Not so pleased that others could just say "I don't know". If you don't, then look it up. It is as simple as putting the phrase into a search engine. eg Wikipedia says: In Judeo/Christian tradition, the term Ivory Tower is a symbol for noble purity. It originates with the Song of Solomon (7,4) ("Your neck is like an ivory tower") (in the Hebrew, Massoretic Bible it is found in 7:5) and was added to the epithets for Mary in the sixteenth century Litany of the Blessed Virgin Mary ("tower of ivory", in latin Turris eburnea). The image is Biblical, and although the term is rarely used in religious sense, it is credited with inspiring the modern meaning.[1] Today, ivory tower usually describes a metaphysical space of solitude and sanctity disconnected from daily realities, where certain idealistic writers endeavor and even some scientists are considered to reside. In Iliad (XIX.560) two kinds of dreams are distinguished, as they exit from the realm of Morpheus: true dreams exit through the Gate of Horn, and false dreams through the Gate of Ivory. Virgil put the image succinctly: There are two gates of sleep. One is of horn, easy passage for the shades of truth; the other, of gleaming white ivory, permits false dreams to ascend to the upper air. (Aeneid VI.893-896)