Q I have an interest in hypnosis. Can you tell me anything about the origin of the word “hypnosis” or “hypnotism”? – G. K., Danbury, Conn.

A: “Hypnosis” comes from a name in Greek mythology, and from the same story that also gives us the word “morphine.” In Greek mythology, Hypnos (in Latin, Somnus) was the god of sleep. The brother of Thanatos (Death) and the son of Nyx (Night), Hypnos lived, according to one tradition, in a land of perpetual darkness and mist. The god’s home was a cavern, through which the waters of Lethe, the river of forgetfulness, flowed.

Surrounding Hypnos, who reclined on a couch, were numerous sons – the Dreams. Prominent among the sons was Morpheus. Hypnos and Morpheus were occasionally called upon to exercise their powers when the chief gods wished to intervene in mortal affairs. Hypnos could induce a state of sleep, and Morpheus had the power to make human forms appear to dreamers.

In 1843, Scottish surgeon James Braid (1795-1860) used the name of the Greek god of sleep to create the term “hypnotism,” which he introduced in his treatise “Neuryphology, or the rationale of nervous sleep.” “Hypnotism” (also known in the 19th century as “Braidism”), the science or practice of artificially inducing a sleep-like trance, gave rise to the coinage of “hypnosis,” the term for the trance itself.

Q I am confused by “all right” and “alright.” How do I know when to use “all right” and when to use “alright”? – T. C., Ludlow, Mass.

A: The short answer is that “all right” and “alright” are synonyms, so you can choose either one. The long answer, though, is that there are important differences between the two words that might influence your choice. First, “all right” is much more common than “alright.” Second, “alright” is much more likely to be found in comic strips, trade journals, and newspapers and magazines than in more literary sources. Third, and maybe most significantly, many people, including the authors of just about every writer’s handbook, think “alright” is all wrong.

The controversy over the appropriateness of “alright” seems to have begun in the early 20th century. Some critics have labeled it illiterate and colloquial, while others have simply denied that it exists. What the critics do not do is offer any compelling reasons for its being considered wrong, apart from its relative newness. (Analogous words like “already” and “altogether” are of course considered perfectly acceptable, but, unlike “alright,” they have been in use for centuries.)

Usage commentators note that “alright” is found more often in manuscript than in print; undoubtedly it would be found more frequently in print if copy editors were not so inclined to change it to “all right.”

Thus “alright” remains a commonly written but less often printed variant of “all right.” If you use it, be prepared to draw some criticism.

Q While we were playing Scrabble recently, my opponent came up with the word “emote.” Is it a slang word? – T. V., Manville, N.J.

A: The word “emote” is not slang. Rather, it is a back-formation from the noun “emotion” that was first recorded in 1917 and is defined as “to express emotion in an exaggerated manner.” We usually see the word “emote” used in reference to acting, as in “A method actor can sit on a stage, feeling deeply and emoting strongly, but it’s no good if the audience hasn’t the faintest idea of what is going on.” However, anyone can emote, simply by giving vent to emotions, whether negative or positive. A quotation from our files exemplifies this extension of meaning: “What will happen to the great old profs who emote from their lecture notes each year?” In any case, “emote” is a legitimate, frequently used word, and you should be able to find it in any good dictionary edited and published in recent decades.

This column was prepared by the editors of Merriam-Webster’s Collegiate Dictionary, Tenth Edition. Readers may send questions to Merriam-Webster’s Wordwatch, P.O. Box 281, 47 Federal St., Springfield, Mass. 01102.