1) BOUGHTEN / BOUGHT
“Bought” is the past tense of “buy,” not “boughten.” “Store-bought,” a colloquial expression for “not home-made,” is already not formal English; but it is not improved by being turned into “store-boughten.”
2) BOURGEOIS
In the original French, a bourgeois was originally merely a free inhabitant of a bourg, or town. Through a natural evolution it became the label for members of the property-owning class, then of the middle class. As an adjective it is used with contempt by bohemians and Marxists to label conservatives whose views are not sufficiently revolutionary. The class made up of bourgeois (which is both the singular and the plural form) is the bourgeoisie. Shaky spellers are prone to leave out the E from the middle because “eoi” is not a natural combination in English; but these words have remarkably enough retained their French pronunciation: boorzhwah and boorzhwazee. The feminine form, “bourgeoise,” is rarely encountered in English.
3) BOUYANT / BUOYANT
Buoys are buoyant. In the older pronunciation of “buoy” as “bwoy” this unusual spelling made more sense. Now that the pronunciation has shifted to “boy” we have to keep reminding ourselves that the U comes before the O.
4) BRAND NAMES
Popular usage frequently converts brand names into generic ones, with the generic name falling into disuse. Few people call gelatin dessert mix anything other than “Jell-O,” which helps to explain why it’s hard to find Nabisco’s Royal Gelatin on the grocery shelves. All facial tissues are “Kleenex” to the masses, all photocopies “Xeroxes.” Such commercial fame is, however, a two-edged sword: sales may be lost as well as gained from such over-familiarity. Few people care whether their “Frisbee” is the genuine Wham-O brand original or an imitation. Some of these terms lack staying power: “Hoover” used to be synonymous with “vacuum cleaner,” and the brand name was even transmuted into a verb: “to hoover” (these uses are still common in the UK). Most of the time this sort of thing is fairly harmless, but if you are a motel operator offering a different brand of whirlpool bath in your rooms, better not call it a “Jacuzzi.”
5) BRANG, BRUNG / BROUGHT
In some dialects the past tense of “bring” is “brang” and “brung” is the past participle; but in standard English both are “brought.”