Questions that can be answered using commonly-available references are off-topic. What good reference works on English are available online, and what kinds of questions are they good at answering?
Useful for finding definitions, etymologies, pronunciations, and examples of usage.
The online dictionaries listed here are those most commonly cited on EL&U. They are broadly suitable for native speakers, providing major definitions and examples, pronunciations (including audio), basic etymology, and some usage notes.
A learner's dictionary is geared to the needs of people learning English as a foreign or second language, for example, by providing notes on usage and common errors. Commonly cited on EL&U are the following:
"Meta-dictionary" is something of a misnomer; it is not a dictionary of dictionaries, but a resource that collects entries from multiple resources in a single place.
Historical and dialectical dictionaries
These dictionaries may be helpful for researching word origins and formation, semantic drift, and historical and regional variations.
Idioms, expressions and slang
There are numerous print dictionaries which focus on idioms, including various offerings by Oxford and McGraw-Hill. Quality online references are rarer.
There are countless resources on slang, including published dictionaries such as the McGraw-Hill Dictionary of American Slang and Colloquial Expressions. By nature, however, slang usage is informal and ephemeral, and difficult to compile into a definitive reference. Most online slang dictionaries must rely on user input, with wildly varying accuracy and reliability. Nevertheless, they are much faster to update than traditional dictionaries, and have dates which help track evolution. Examples include the Online Slang Dictionary, edited by Walter Rader; A Dictionary of Slang by Ted Duckworth; and probably the most popular, Urban Dictionary.
Useful for finding word usages and collocations.
Useful for finding synonyms of specific words.
General Language and English Language Reference
Both are written and edited by David Crystal. They should be in every Anglophone classroom in the world, and should be consulted first about questions bearing on English.
All works by David Crystal are trustworthy, but these encyclopedias are really well-organized, and full of useful information.
The guidelines governing the presentation of written English are collectively referred to as style, and laid out in various rulebooks and manuals. The purpose of these guidelines is to provide a uniform presentation, to improve readability and as a mark of professionalism. Some industries, such as screenwriting, use specific formats, but any individual organization or even an individual publication can enforce a house style. If a writer has not been directed to follow a particular style or other guidelines, s/he is encouraged to choose a suitable style and be consistent in its use.
For example, organizations and editors may differ, for example, on whether to hyphenate African American, if toward should be capitalized in a title, when to use USSR as opposed to Soviet Union, cases where Hellenic should be used instead of Greek, or whether and when to spell adviser as advisor. Because many such questions of punctuation, capitalization, abbreviation, citation, diction, and even spelling can only be answered within a narrow context, many questions about these topics posted to EL&U will be closed as primarily opinion-based, or for demonstrating a lack of basic research.
A collection of online style guides is provided by OnlineStylebooks.com, providing a search engine and the ability to sort style guides by field and by name.
General Style Guides
Of the most popular general style guides, only Oxford and Chicago are available online, and only with a subscription.
Academic Style Guides
Journalist Style Guides
Governmental Style Guides
Note: No government of any major English-speaking country attempts to enforce English style or usage as a matter of law or regulation. These guides are published mainly for writers in the employ of the respective governmental office or body.
Older style guides tend to be strongly prescriptive, that is, flatly asserting that certain usages are wrong even if they are widely used and well-understood. Some recommendations or cautions have been transformed and transmitted over the years as "rules" that are rejected by professional writers and linguists alike, such as the prejudice against the passive voice or against ending sentences with prepositions. Therefore, writers must be cautious about the stylistic advice given in popular guides like Strunk and White’s The Elements of Style, or older editions of Fowler's.
Dictionaries and Lexica
Machine translations are generated by computer software which compares parallel texts produced by human translators and attempts to identify patterns and apply them to submitted text. The result can be helpful for short, simple text, but is often inaccurate, unidiomatic, or flat-out incorrect, and so should be used with caution.
This seems to be very good marketing for University of Chicago Press, or whoever made this decision, because it gives a good and useful sample of what's in the book. The first three chapters are the general ones, where the author lays out the methodology, definitions, examples, and tests for syntax. They're all most people need to read; the other chapters are specialized on individual construction types and other issues.
These chapters consist of
1. (pp 1-10) Introduction
There are useful tree diagrams and excellent example sentences throughout. Anyone familiar with what's in these three chapters has gone a long way toward mastering English syntax.
McCawley's book is very clear, but it is a technical scientific work intended as a college textbook for a year-long course. It's not necessary to understand linguistics to benefit from the book; however, readers will have to understand that spoken English is what grammar, and therefore this book, is about. There is no treatment of spelling, punctuation, or "correct" grammar, for instance. These are not syntactic phenomena, but social ones.
Huddleston and Pullum covers everything -- including, for example, a chapter on punctuation by Geoffrey Nunberg -- and introduces a number of terminological innovations that may become widely-accepted in a while; my advice is to be wary of the terminology -- learn it, and learn the alternative terms as well. They are discussed as they are introduced.
E.g, what McCawley calls a "restrictive relative clause", Pullum and Huddleston call an "essential relative clause"; what McC calls a "particle" up in phrasal verbs like pick up, P&H call an "intransitive preposition" up. You will find both sets of terms (among many others, from all over the world) used here on EL&U.
Okay, I guess I should have added my answers here instead of above in the comments. So, I'll try again.
Dictionary.com gives all the source references on one page, from English and slang to science, computing, and medical dictionaries, including History and Origin, all from specific dictionaries. It includes nearby words, related searches, and all words from the root.
RhymeZone.com gives rhymes, thesaurus, similar sounding words, quotations, homophones, letter matching search, pictures, and even Shakespeare references. It has links to the Bible books, and famous quotes, and several links to specific genres produced by Shakespeare. I use this site almost daily.
I recommend the site EngVid for clearing up questions about grammar rules, and other English language dilemmas. There are videos for over 500 subjects on that site, all related to English. Some people learn better through watching demonstrations on whiteboard. These videos work well for tutoring, too.
I also believe you need a link to the Middle English Dictionary. It may be an obscure language, but we still study the Canterbury Tales by Chaucer, and John Gower's Confessio Amantis.
For the word you search, it has:
Dissection or Parse of Sentences