thorn cluster

plural thorn clusters

1. Indo European studiesOne of three consonant clusters historically believed by some scholars to have existed in Proto-Indo-European, all of which ended with the IPA sound [θ] (often symbolized by the letter thorn, ⟨þ⟩).
   1. Indo European studiesAny of the reconstructed consonant clusters that have replaced the original thorn clusters in modern scholarship, which typically no longer contain the sound [θ].