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plus (plŭs)
1. Mathematics Increased by the addition of: Two plus two is four.
2. Added to; along with: Their strength plus their spirit makes them formidable. Intelligence plus wit makes for an interesting person.
3. Usage Problem And: "[He] is a committed man, plus he has imagination, vitality and national stature" (Merv Griffin).
1. Positive or on the positive part of a scale: a plus value; a temperature of plus five degrees.
2. Added or extra: a plus benefit.
3. Informal Increased to a further degree or number: "At 70 plus, [he] is old enough to be metaphysical" (Anatole Broyard).
4. Ranking on the higher end of a designated scale: a grade of C plus.
5. Physics Positive.
6. Plus-size.
n. pl. plus·es or plus·ses
1. Mathematics The plus sign (+).
2. A positive quantity.
3. A favorable condition or factor: The clear weather was a plus for the golf tournament.

[Latin plūs, more; see pelə-1 in the Appendix of Indo-European roots.]

Usage Note: When mathematical equations are pronounced as English sentences, the verb is usually in the singular: Two plus two is (or equals) four. By the same token, subjects containing two noun phrases joined by plus are usually construed as singular: The construction slowdown plus the bad weather has made for a weak market. This observation has led some to argue that in these sentences, plus functions as a preposition meaning "in addition to." But if this were true, the plus phrase could be moved to the beginning of the sentence. Clearly, this is not the casewe do not say Plus the bad weather, the construction slowdown has made for a weak market. It makes more sense to view plus in these uses as a conjunction that joins two subjects into a single entity requiring a single verb by notional agreement, just as and does in the sentence Chips and beans is her favorite appetizer. · The use of plus introducing an independent clause has long been considered infelicitous, if not wrong. But a clear majority of the Usage Panel accepts it. In our 2009 survey, 67 percent accepted the example He has a lot of personal charm. Plus, he knows what he's doing. Some 63 percent accepted an example expressing negative judgment: We were a terrible team. Plus, we had bad uniforms.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.