mainyoudaoicibaDictYouDict[main 词源字典]
main: [OE] Main goes back to prehistoric Germanic *mag- ‘be able, have power’ (source also of English may and might, and distantly related to machine). From it was descended Old English mægen ‘strength’. This now survives as a noun only in the expression with might and main, but it was also used attributively in Old English to mean ‘of large size, great’, and by the 13th century (helped along partly by the related Old Norse megenn or megn ‘strong’) it was being used as an adjective in its own right. At first it still meant just ‘large’, but by the 15th century its modern sense ‘chief’ had evolved.
=> may, might[main etymology, main origin, 英语词源]
main (n.)youdaoicibaDictYouDict
Old English mægen (n.) "power, bodily strength, force, efficacy," from Proto-Germanic *maginam "power," suffixed form of PIE root *magh- (1) "be able, have power" (see may (v.)). Original sense preserved in phrase with might and main. Meaning "principal channel in a utility system" is first recorded 1727 in main drain. Used since 1540s for "continuous stretch of land or water;" in nautical jargon used loosely for "the ocean," but in Spanish Main the word is short for mainland and refers to the coast between Panama and Orinoco (as contrasted to the islands of the West Indies).
main (adj.)youdaoicibaDictYouDict
early 13c., "large, bulky, strong," from Old English mægen- "power, strength, force," used in compounds (such as mægensibb "great love," mægenbyrðen "heavy burden;" see main (n.)), probably also from or influenced by Old Norse megenn (adj.) "strong, powerful." Sense of "chief" is c. 1400. Main course in the meal sense attested from 1829. Main man "favorite male friend; hero" is from 1967, U.S. black slang.