Eð is an Icelandic letter. It is never at the beginning of a word, so you will rarely see its capital version Ð. It makes a soft th sound like “father” while it’s cousin the Þþ makes a strong th sound as in “method”. Unlike ð, þ usually comes at the beginning of words.
Icelandic words with ð include: að (to), bað (bath), tað (dung), faðir (father), móðir (mother), góðir (good), fóður (feed (n.)), maður (man), maðkur (worm), borð (table) and Vaðlaheiðarvegavinnuverkfærageymsluskúraútidyralyklakippuhringur.