rightfully

From Middle English ryghtefully, equivalent to rightful +‎ -ly.

• IPA^(key): /ˈɹaɪtfəli/

rightfully (comparative more rightfully, superlative most rightfully)

1. In accordance with what is right or just; fairly.
   • 1859, John Stuart Mill, “Introductory”, in On Liberty, London: John W[illiam] Parker and Son, […], →OCLC, page 22:

     [T]he only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others. His own good, either physical or moral, is not a sufficient warrant.

2. Rightly, correctly.
   • 1590, Edmund Spenser, “Book II, Canto VIII”, in The Faerie Queene. […], London: […] [John Wolfe] for William Ponsonbie, →OCLC, stanza 21, page 296:

     Ne euer will it [King Arthur's sword] breake, ne euer bend. / Wherefore Morddure it rightfully is hight.

     The sword is more commonly known as Excalibur.