Which of these words are in good use?

Pianist, harpist, poloist, violinist, phiz, ad, co-ed, curios, exam, cab, chum, gent, hack, gym, pants, mob, phone, proxy, photo, prelim, van, prof, varsity.

Misused Nouns.[22]—Many errors in English consist in using words in senses which are not authorized. Sometimes the use of a word in a wrong sense makes the speaker's meaning obscure. Sometimes it makes him seem ridiculous, as when a person of the writer's acquaintance told a friend to clean an oil-painting by washing it in "torpid" water.In every case the misuse of a word leaves an unpleasant impression on the mind of a cultivated person, and, like all bad English, should be avoided as we avoid bad manners. In the following definitions and exercises a few nouns[23] are selected for study. The distinctions given are not always observed by reputable authors, but they indicate the tendency of the best modern usage.

I. A RESEMBLANCE IN SENSE MISLEADS.[24]

House, home.—A house is a building. Home means one's habitual abode, "the abiding place of the affections." It may or may not be in a house, and it may include the surroundings of a house.

Person, party.—A person is an individual, a party is a company of persons, or, in legal usage, a person who is concerned in a contention or agreement.

Series, succession.—A series is a succession of similar things mutually related according to some law. Succession is properly used of several things following one after the other; it denotes order of occurrence only, and does not imply any connection.

Statement, assertion.—A statement is a formal setting forth of fact or opinion; an assertion is simply an affirmation of fact or opinion.

Verdict, testimony.—A verdict is a decision made by a number of men acting as a single body. Testimony is an expression of individual knowledge or belief.

The whole, all.The whole is properly used of something which is considered as one thing. When a number of persons or things are spoken of, the proper word is all.