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Containing a group of four carbon atoms: butyl.


The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
but (bŭt; bət when unstressed)
1. On the contrary: the plan caused not prosperity but ruin.
2. Contrary to expectation; yet: She organized her work but accomplished very little. He is tired but happy.
3. Usage Problem Used to indicate an exception: No one but she saw the prowler.
4. With the exception that; except that. Often used with that: would have joined the band but he couldn't spare the time; would have resisted but that they lacked courage.
5. Informal Without the result that: It never rains but it pours.
6. Informal That. Often used after a negative: There is no doubt but right will prevail.
7. That ... not. Used after a negative or question: There never is a tax law presented but someone will oppose it.
8. If not; unless: "Ten to one but the police have got them" (Charlotte M. Yonge).
9. Informal Than: They had no sooner arrived but they turned around and left.
Usage Problem Except.
1. Merely; just; only: hopes that lasted but a moment.
2. Used as an intensive: Get out of here but fast!
A concern or objection: My offer is final, no ifs, ands, or buts.
but for
Were it not for: except for: We would have reached the summit but for the weather.

[Middle English, from Old English būtan; see ud- in the Appendix of Indo-European roots.]

Usage Note: Traditional grammarians have worried over what form the pronoun ought to take when but is used to indicate an exception in sentences such as No one but I (or No one but me) has read it. Some have argued that but is a conjunction in these sentences and therefore should be followed by the nominative form I. However, many of these grammarians have gone on to argue somewhat inconsistently that the objective form me is appropriate when the but phrase occurs at the end of a sentence, as in No one has read it but me. In fact, there is a strong case for viewing but as a preposition in all of these constructions. For one thing, if but were truly a conjunction, the verb should agree in person and number with the noun or pronoun following but, and so the verb should always be plural when the noun or pronoun following but is plural. It would thus be correct to say No one but the students have read it, even though no one is normally treated as a singular. What is more, a conjunction cannot be moved to the end of a clause, as a prepositional phrase can be, as in No one has read it but the students. By comparison, the conjunction and cannot be repositioned in this way. That is, it is not grammatical to say John left and everyone else in the class. For these reasons it seems best to consider but as a preposition in these constructions and to use the objective forms of pronouns such as me and them in all positions. A large majority of the Usage Panel agreed with this policy as long ago as 1988, when only 17 percent accepted No one has read it but I, and 30 percent accepted No one but I has read it. The use of me was acceptable to 70 percent of the Panel when the but phrase preceded the verb, and to 90 percent when the but phrase followed the verb. · But is redundant when used together with however, as in But the army, however, went on with its plans; one or the other word should be eliminated. · But is generally not followed by a comma. Correct written style requires Kim wanted to go, but we stayed, not Kim wanted to go, but, we stayed. · But may be used to begin a sentence at all levels of style. See Usage Notes at and, cannot, doubt, however, I1.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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