magnitudeyoudaoicibaDictYouDict[magnitude 词源字典]
magnitude: [14] Magnitude is one of a large family of words for which English is indebted to Latin magnus ‘large’. This goes back to an Indo- European *meg- or *megh-, source also of Greek mégas ‘large’ (from which English gets the prefix mega-) and prehistoric Germanic *mikil-, ancestor of English much. Apart from magnitude, English descendants of magnus include magnanimous [16] (etymologically ‘large-minded’), magnate [15] (a ‘large’ or ‘important’ person), magnificat [12] (from the first words of Luke 1:46, Magnificat anima mea dominum ‘My soul doth magnify the lord’, where magnificat is the 3rd person present singular of Latin magnificāre, a derivative of magnus and source of English magnify [14]), magnificent [16] (etymologically ‘doing great deeds’), and magnum [18] (the application to a double-sized wine bottle is a modern one).

In addition maxim and maximum come from the superlative of magnus and major and mayor from its comparative, and master and the monthname May could also be related.
=> magnum, major, maxim, mayor, much[magnitude etymology, magnitude origin, 英语词源]
magnitude (n.)youdaoicibaDictYouDict
c. 1400, "greatness of size or character," from Latin magnitudo "greatness, bulk, size," from magnus "great" (see magnate) + -tudo, suffix forming abstract nouns from adjectives and participles (see -tude). Meaning "size, extent" is from early 15c. Of stars, "brightness," from 1640s.