aquiline: eagle-like, probably referring to the curve of the nose and chin.
astrakhan: a lambskin with tightly curled wool, as produced in the Russian city of Astrakhan.
beryl: a mineral whose varieties include emerald and aquamarine.
bijou villa: literally, "a small jewel of a house" (French).
Bohemia: the area surrounding Prague, today in the Czech Republic, then a part of the Austro-Hungarian Empire. The notion of Bohemia as a separate country, with a hereditary ruling family, is the author's invention.
Bohemian soul: an unconventional person (from an association between Bohemia and Gypsies). The description of Holmes is ironic, considering that this story will deal with the King of Bohemia.
Boswell: biographer, chronicler; after James Boswell (1740-95), whose Life of Johnson, about the writer and lexicographer Samuel Johnson (1709-84), is still perhaps the most famous biography in English.
brougham: a closed four-wheeled carriage with the driver's seat outside in the front.
burned: as in, "burned at the stake." Watson is suggeting that Holmes's powers of deduction would have made him seem a sorcerer or witch in an earlier time.
cabinet: with its mounting, a cabinet photography was about the size of a modern 5" x 7".
cabman: the driver of a cab or carriage.
Carlsbad: or Karlsbad, a famous spa and resort in what is today the Czech Republic.
carte blanche: literally, "white card" (French), meaning "blank check" or full freedom and authority to do as one sees fit.
chamois leather: originally, the skin of the small chamois antelope, and later any soft leather from the skin of a sheep, deer, or goat.
Charing Cross: a major London train station
Chubb lock: a prominent British brand at the time.
civil practice: Watson has been a medical officer in the British Army; following his marriage in the previous Holmes adventure, The Sign of Four, he moves out of the rooms at 221B Baker Street which he shared with Holmes, and begins a non-military ("civil") medical practice.
cocaine: Cocaine common and legal in Europe and the United States until early this century. Sigmund Freud, for example, at first considered it something of a wonder drug, using it himself and prescribing it for others, before changing his mind because of its addictive qualities. And the original formula of Coca-Cola contained cocaine. Holmes drinks his cocaine dissolved in water, and from Watson's descriptions it is clear that Arthur Conan Doyle understood the dangers of the drug.
Contralto, La Scala, Prima donna Imperial Opera of Warsaw:
contraction: that is, an abbreviation.
two crimes: that is, A Study in Scarlet and The Sign of Four, the two previously published Sherlock Holmes novels.
crown: a silver coin worth five shillings, so called because it bore the image of a crown on one side. "Half a crown" would have been worth two shillings and sixpence.
Darlington substitution scandal, Arnsworth Castle business: apparently, two of Sherlock Holmes' unrecorded cases.
Edgeware Road: a major London road, running northwest from Hyde Park.
Egria: a fictitious country whose name is based on the town of Eger, where Wallenstein was assassinated.
four-wheeler: an enclosed carriage with four wheels and doors on both sides; the driver usually sat in the front on top.
freemasonry: a natural sympathy or understanding among people in similar positions, as if they belonged to a secret society like the Freemasons.
gasogene: a kind of soda syphon, used to add carbonation to water and other liquids.
gibe: a taunting or scoffing remark; also spelled "jibe."
groom: a person who feeds and cares for a horse.
guineas: gold coins worth twenty-one shillings (or one pound and one shilling), so-called because gold was associated with Guinea, in Africa. Though the coin was last minted in 1813 (and so was long out of circulation even by the time the Sherlock Holmes stories were written), the term continues to be used in Britain to suggest luxury or liberality. "Half a guinea" would be worth ten shillings and sixpence.
half and half: a mixture of two drinks, such as porter and ale, or beer and stout.
hansom: a horse-drawn covered carriage for two passengers, with the driver's seat above and behind.
Mr. John Hare: Hare (1844-1921) was a prominent English actor at the time.
go into harness: to go to work.
Hercules: the strong man of Greek mythology.
horsy: having to do with vehicles and the horses that pulled them.
House of Ormstein: the fictitious ruling family of the fictitious country of Bohemia.
incognito: disguised or using an assumed identity
iodoform: a crystalline compound of iodine used as an antiseptic.
landau: a four-wheeled, covered carriage, with the cover split into two section, both of which can be opened.
Langham: One of the finest hotels in London at the time.
Majesty: a form of address used only for a sovereign ruler.
mews: a stable built along a court or alley.
nitrate of silver: a crystalline salt used as an antiseptic, and also in the process for silver plating and photography.
Non-conformist clergyman: all Protestant groups who choose not to associate themselves with England's official Anglican church are called "non-conformist."
Odessa: a port and resort on the Black Sea, then in Russia and now in the Ukraine. The "case of the Trepoff murder" is apparently one of Holmes's unrecorded cases.
ostlers: the cockney pronunciation of "hostlers," or those who work at a stable for horses.
Prague: The largest city in Bohemia, then a city in the Austro-Hungarian empire, today the capital of the Czech Republic.
Regent Street: then, as now, one of the most prominent business districts of London.
St. John's Woods: a neighborhood due west of Regent's Park, in the northwest section of the London.
King of Scandinavia: Scandinavia is a region (comprised of Denmark, Sweden, Norway, and Iceland), but it has never been a country, and it has no king.
shag: a cheap, shredded cut of tobacco.
The Sign of Four: title of an 1890 Sherlock Holmes novel.
smoke-rocket: a smoke bomb used by plumbers to detect leaks in pipes.
sovereign: a coin worth one pound sterling, so called because it carried a likeness of an English king or queen. "Half a sovereign" would be worth ten shillings.
spirit case: a cabinet filled with flasks containing various distilled liquids and solutions.
stethoscope: a medical hearing instrument, used to examine the heart, lungs, and other organs by listening to the sounds they make.
strong character: the author apparently subscribed to physiognomy, the belief that character and mental abilities were expressed in facial features.
A Study in Scarlet: title of the first Sherlock Holmes novel (1887).
surpliced: wearing the white ritual cloak, or surplice, of an Anglican priest.
Inner Temple: one of the Inns of Court, where London's legal profession lived and worked.
Trincomalee: a fortified port on what was then the British island colony of Ceylon, and is now the country of Sri Lanka, south of India. The "tragedy of the Atkinson brothers" is apparently one of Holmes's unrecorded cases.
ulster: a long, heavy overcoat of a type original produced in northern Ireland.
verbs: a reference to German syntax, in which the verb, often compounded, usually ends the sentence.
vizard: a mask that only covers, or shields, the eyes.
Wallenstein: Albrecht Eusebius Wensel von Wallenstein, Duke of Friedland, was assassinated in Eger, now in the Czech Republic, in 1634, during the Thirty Years' War.