厂 (to announce) + 一 + 口 (a mouth). It represents the powerful queue gives orders.
Han character 
This character is present in both Traditional and Simplified Chinese. However, it only means "after" or "behind" when it is simplified due to the merging of characters 后 and 後 in Simplified Chinese. The latter is used to represent "after" in Traditional Chinese.
- KangXi: page 176, character 1
- Dai Kanwa Jiten: character 3298
- Dae Jaweon: page 393, character 1
- Hanyu Da Zidian: volume 1, page 580, character 1
- Unihan data for U+540E
后 (hangeul 후, revised hu, McCune-Reischauer hu, Yale hwu)
- after; following; behind
Han character