This book provides detailed glosses on ancient characters.
Tips
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Almost only seen in the compound 训诂 xùngǔ — the traditional Chinese philological discipline of explaining the meaning of ancient words. The 《说文解字》 entry says 诂 = 'glossing ancient speech', and 《毛诗诂训传》 of the Han dynasty is the canonical model.
memory
Speech radical 讠 plus 古 (ancient) — speaking about the ancient: explaining old words.
