Comprehensive English Dictionaries and the OED second edtion

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Hello. I am interested in purchasing English Language Dictionaries. What is the difference between comprehensive and unabridged?
What comprehensive and/or unabridged English language dictionaries have the same and/or similar features as the OED second edition? i'm looking for dictionaries that feature archaisms, psuedoarchaisms, colloquialisms, various spellings of words, synonyms, poetic words, unusual words, slang words, words from literature and history and mythology, etymologies, definitions of words in the etymologies, word usages (fig., transfigurative., metaphoric, poetic, allusive., attrib., etc.) and citations and quotes and words borrowed from other languages/cultures? And Spencerian and Chaucerian words? Please let me know. Thank you.