== 語源 ==
モリガンの名前の意味には異論もある。モリガンの名前の意味には異論もある。Morは古英語のmaere(現代英語の「悪夢」に残っている)やスカンジナビア語のmara、古東スラヴ語の「mara」(「悪夢」)と同系の恐怖や怪物を意味するインドヨーロッパ語源に由来すると考えられる<ref>DIL, 1990, pp467–468</ref>が、ríganは「女王」と訳されている<ref>DIL, 1990, p507</ref><ref name="maryjones.us">[https://www.maryjones.us/jce/morrigan.html Jones Celtic Encyclopedia Entry: ''Morrigan'']</ref>。
There is some disagreement over the meaning of the Morrígan's name. ''Mor'' may derive from an [[Indo-European languages|Indo-European]] root connoting terror, monstrousness [[cognate]] with the [[Old English]] ''maere'' (which survives in the modern English word "nightmare") and the Scandinavian ''[[mare (folklore)|mara]]'' and the [[Old East Slavic]] "mara" ("nightmare");{{sfn|DIL|1990|pp=467–468}} while ''rígan'' translates as "queen".{{sfn|DIL|1990|p=507}}<ref name="maryjones.us">[https://www.maryjones.us/jce/morrigan.html Jones Celtic Encyclopedia Entry: ''Morrigan'']</ref> This etymological sequence can be reconstructed in the [[Proto-Celtic language]] as *''Moro-rīganī-s''.<ref>{{cite web |url=http://www.st-andrews.ac.uk/institutes/sassi/spns/ProtoCelt.pdf |title=Proto-Celtic – English wordlist |archive-url=https://web.archive.org/web/20070927041947/http://www.st-andrews.ac.uk/institutes/sassi/spns/ProtoCelt.pdf |archive-date=27 September 2007}}</ref><ref>{{cite web |url=http://www.etymonline.com/index.php?term=nightmare |work=EtymologyOnline |title="nightmare"}}</ref> Accordingly, ''Morrígan'' is often translated as "Phantom Queen".<ref name="maryjones.us"/> This is the derivation generally favoured in current scholarship.{{sfn|Clark|1990}}
In the [[Middle Irish]] period, the name is often spelled ''Mórrígan'' with a lengthening diacritic over the ''o'', seemingly intended to mean "Great Queen" (Old Irish ''mór'', "great";{{sfn|DIL|1990|pp=467–468}} this would derive from a hypothetical [[Proto-Celtic language|Proto-Celtic]] *''Māra Rīganī-s'').<ref>Alexander McBain, ''An Etymological Dictionary of the Gaelic Language'', 1911: ''[http://www.ceantar.org/Dicts/MB2/mb27.html#mór mór]'', ''[http://www.ceantar.org/Dicts/MB2/mb30.html#rìbhinn ribhinn]''</ref> [[Whitley Stokes]] believed this latter spelling was due to a [[false etymology]] popular at the time.<ref>{{cite book |author-link=Whitley Stokes |last=Stokes |first=Whitley |year=1891 |chapter=Notes to "The Second Battle of Moytura" |title=[[Études Celtiques]]'' xii |page=128}}</ref> There have also been attempts by modern writers to link the Morrígan with the [[Welsh-language literature|Welsh literary]] figure [[Morgan le Fay]] from the [[Matter of Britain]], in whose name ''mor'' may derive from Welsh word for "sea", but the names are derived from different cultures and branches of the Celtic linguistic tree.{{sfn|DIL|1990|pp=467–468}}