In France, there is a permanent appointed committee to regulate use of French, and likewise in Spain with Spanish. It is the job of committee members to determine how words should be spelled and used. The committee members blacklist words and meanings that they find unacceptable (which often are words of foreign origin), and seek acceptable alternatives. The idea is to maintain the purity of the language, which doubtless is seen as an art form. Official dictionaries of those two languages give the spellings and meanings of approved words.
English is a hybrid language with 3 major origins: (1) Anglo-Saxon, (2) Norse, and (3) Latin. Some of the Latin words came directly from Latin, and others first became Norman (or later) French before being adopted. English has a rich vocabulary (for example, anger/wrath/ire are synonyms from the three origins) because of its hybrid nature. English grammar and pronunciation are highly irregular for the same reason. English has almost always been free to evolve without interference from a national language committee. Spellings were wildly variant before the first (18th century) dictionaries began to record and standardize them. However, in the USA in the late 18th and early 19th centuries, Benjamin Franklin and Noah Webster tried to differentiate US English from English English by devising spellings different from those used in England, as a matter of patriotism. Webster later reversed his decision and tried (not entirely successfully) to reintegrate the spellings. These changes account for almost all the spelling differences between English used in the USA and that used in the rest of the English-speaking world (now more than 50 other nations).
Editors/publishers of English-language dictionaries, unregulated by any national or international committee, however, bear a great responsibility by the selection of the words they list. The general policy of editors is now to retain most old words (rejecting a few as being too archaic), and add new meanings that people attribute to words, thus adding new meanings for such words as cool as a synonym of debonair, and presently as a synonym for now. It is also to add newly-invented words (e.g., quark), and words adopted from other languages (e.g., tortilla).
Editors of English-language dictionaries likewise bear a great responsibility by the spelling of the words they list. The general policy is now to retain traditional spellings (now with a very slight difference between spellings in the USA and those in the rest of the English-speaking world), and to add words of foreign origin with the spellings used in that foreign language (if it uses the Roman alphabet). In general, obvious misspellings are simply omitted.
Pronunciation of words is treated by English-language dictionaries. But that mine-field is not addressed here. [see, however, Section 22]
The Oxford English Dictionary (OED) is by far the biggest and most thorough dictionary of the English language (the 1971 edition is a multi-volume set of over 16,400 pages). Not only does it record how words are spelled in all English-speaking countries, but it records the origin and earliest uses of each word. Of course it shows meanings and spellings in the USA (and Canada, Australia, etc.) as well as in Britain. Oxford University Press also publishes an Oxford American Dictionary (OAD), in which US spellings and pronunciations are used for all words.
"Webster's dictionary" is the acknowledged standard dictionary in the USA. Unfortunately, the name "Webster's" is not copyright, so any company may publish under this name. The biggest US-produced dictionary is "Merriam-Webster's New International Dictionary" (M-WNID) with third edition still being reprinted in the 1990s (a single volume of 2,662 pages). Although large, it is greatly simplified as compared with the OED, contains many fewer words, and does not give a history/explanation of their use. It shows the spellings used in the USA, but adds spellings used in other English-speaking countries. WWWebsters Dictionary) [http://www.m-w.com/cgi-bin/mweb] is an on-line dictionary based on Merriam-Webster's Collegiate Dictionary (10th edition) which is much smaller than M-WNID.
1. Some North American scientific journals state that they require people who submit manuscripts to use "Webster's dictionary" as a spelling guide. That means, for example, use the spellings color and program and theater, which are now traditional in the USA due to Webster (except in New York city, where the spelling theatre is normal), and not the spellings colour and programme and theatre which are the norm in other parts of the English-speaking world. Few authors would argue with that requirement, nor that in other English-speaking countries they should write those words as colour and programme and theatre. Unfortunately, these edicts do not say which version of "Webster's dictionary" they want to be used. This causes confusion about a few words. The US editors would do better to state: use US spellings where they differ from British as shown in the latest editions of OED or M-WNID, or use OAD or WWWebsters.
2. Spellings used in English-language dictionaries depend on
the expertise of the editorial staff, which is not infallible.
Two apparent errors in Merriam-Webster's dictionaries are probed
here.
(a) WWWebsters records the spelling "weiner" as a "variant"
spelling of "wiener", but also presents all the necessary
evidence (derivation from the German adjective wiener) why no
spelling other than "wiener" should be accepted. So
why does "Webster's" even bother to list "weiner",
which is simply a misspelling?
(b) WWWebsters records the spelling "predaceous" as
a main entry and gives "predacious" as a secondary spelling.
Why is this so when the OED presents copious etymological evidence
(and refuses to show "predaceous" as an entry) to demonstrate
that "predaceous" is a misspelling?
3. It would help communication if international publishers
of English-language dictionaries would (with publicity and support
by the international press) meet to standardize English spellings.