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But is a common conjunction in English used between two or more clauses, which often implies the immediately following clause will be the limit, difference, or focal point of the original clauses. Wikipedia does not have an article with this exact name. ... Wiktionary (a portmanteau of wiki and dictionary) is a multilingual, Web-based project to create a free content dictionary, available in over 150 languages. ... The English language is a West Germanic language that originates in England. ...

The usage of but varies. For example:

"It was then but a short step to the idea of selective breeding to improve distribution."

The "but" in this sentence implies that the majority of the involvement in coming to the "idea" had been done. The "but" refers back to whatever steps have been mentioned - probably in the sentence immediately preceding this, and it was probably a very detailed or long process which was described. The inference is that what is left to do - mentally or physically - is probably less than 5% of the overall task. This sort of construction is commonly used to describe how, although A did a huge amount of work on a project, B actually finished it - by being the one to take that last step.

There has been a debate by some about whether the following first person singular pronoun following the word but should be the nominative form I or the accusative form me People that have argued that the pronoun following but should be the nominative pronoun form I have argued that the word but is a conjunction in these sentences, rather than a preposition. The debate has gone on by many about whether the accusative form me is appropriate when the but phrase occurs at the end of a sentence, as in "no one has seen it but me".

An argument has been made while there is considerable weight of precedent on the side of it, and that it cannot be regarding as being incorrect, that there can be a strong case that "but" can be treated as a preposition, because, the verb following the word "but" would be expected to agree in both number and person with the noun or pronoun, if it were truly a conjunction.

The Oxford English Dictionary reveals that the word but is from the Old English be-uton (Compare Dutch buiten, meaning outside) meaning "on the outside, without" In Middle English, this became bouten and then was gradually phonetically weakened to buten, bute and thus but. The Old English word be-uton is itself a combination of the modern word be and uton, which is a form of ut, which is an early form of modern out. It is a call for whatever follows the word to go away or threaten whatever preceded the word. It says that two reactions that do exist cannot coexist and still be associated with effective action. The Oxford English Dictionary print set The Oxford English Dictionary (OED) is a dictionary published by the Oxford University Press (OUP), and is generally regarded as the most comprehensive and scholarly dictionary of the English language. ... Old English (also called Anglo-Saxon[1], Old English: ) is an early form of the English language that was spoken in parts of what is now England and southern Scotland between the mid-fifth century and the mid-twelfth century. ... Middle English is the name given by historical linguistics to the diverse forms of the English language spoken between the Norman invasion of 1066 and the mid-to-late 15th century, when the Chancery Standard, a form of London-based English, began to become widespread, a process aided by the...