What is the meaning of Ð?

a voiced dental fricative or, occasionally, approximant.

[ð]-fricated release of a plosive (e.g. [dᶞ], sometimes implying an affricate [d͜ð]); [ð]-coloring; or a weak, fleeting or epenthetic [ð].

An alveolar tap (IPA ɾ).

Replaces th for an archaic style.

The fifth letter of the Elfdalian alphabet, written in the Latin script.

eth, a letter of the Old English alphabet representing /θ/, which was pronounced [θ] or [ð]

A letter of the Osage Latin alphabet.

The fifth letter of the Faroese alphabet, called edd and written in the Latin script.

The fifth letter of the Icelandic alphabet, called eð and written in the Latin script.

Source: wiktionary.org