(Sherlock fandom slang) A subgenre of Sherlock fan fiction and fanart portraying Sherlock Holmes as a tuna or tuna-headed reverse mermaid.

Alternative form of Badong

Alternative form of Guangdong

Alternative form of Dongguan

Alternative form of Shandong

plural of tunnel boring machine

(engineering) A large machine used to excavate tunnels with a circular cross section.

(slang) A cat that has developed a strong preference for tuna and may refuse to eat anything else.

plural of tuna junkie

(informal) A piercing in the earlobe which has been deliberately stretched to achieve a larger gauge. / (informal) A short, hollow, cylindrical piece of jewellery worn in such a piercing.