Eth (Ð, ð; also spelled edh or ) is a letter used in Old
English, Icelandic, Faroese (in which it is called edd), and
Dalecarlian. It was also used in Scandinavia during the Middle
Ages, but was subsequently replaced with dh and later d. The
capital eth resembles a D with a line partially through the
vertical stroke. The lowercase resembles an insular d with a
line through the top.  The letter originated in Irish writing
(Freeborn 1992, 24) as a d with a cross-stroke added. The
lowercase version has retained the curved shape of a medieval
scribe's d, which d itself in general has not (but see for
instance the Audi logo).  In Icelandic, ð represents a voiced
dental fricative like th in English "them"; however, the name of
the letter is pronounced , i.e., voiceless, unless followed by a
vowel. It has also been labeled an "interdental fricative.  In
Faroese, ð isn't assigned to any particular phoneme and appears
mostly for etymological reasons; however, it does show where
most of the Faroese glides are, and when