tiddler
/ˈtɪdlə(r)/noun
1- Brit. informal a small fish, especially a stickleback or minnow〈英, 非正式〉小鱼（尤指刺鱼、米诺鱼）。
1.1
- a young or unusually small person or thing小娃娃; 异常小的人（或物）。
词源
late 19th cent.: perhaps related to TIDDLY2 or tittlebat, a childish form of stickleback.