What is the meaning of ᚦ?

A letter of the Runic alphabet, present in the Elder Fuþark, the Anglo-Saxon Fuþorc (called þorn), and the Younger Fuþark (called þurs), representing /θ/ or /ð/ and associated with a giant (in the Old Norwegian and Old Icelandic rune poems) or a thorn (in the Anglo-Saxon one).

the third letter of the Old English runic alphabet, representing ⟨þ⟩ and pronounced þorn (“thorn”); equivalent to the letter þ

Source: wiktionary.org