Etymology
Today it means: a ligature of Shavian alphabet letters 𐑭 and 𐑮, representing English /ɑːr/. Full definition →
Ligature of the letters ⟨𐑭⟩ /ɑː/ and ⟨𐑮⟩ /r/.
Etymology from Wiktionary, CC BY-SA 4.0.