command, (kokuji)
諚 centers on an authoritative directive: a command. It is a kokuji, so its meaning is specifically Japanese.
諚 is a kokuji created in Japan, combining 言 (word, speech) with 定 (determine, decide) to express a command or decree. The exact historical development is uncertain, but the component choice fits the meaning.
Words (言) that determine (定) what must be done: a command. Picture a scroll with 言 on the left and the firm decision 定 on the right, issuing an order.
For ジョウ, imagine a commanding officer named Joe giving orders: Joe -> ジョウ, and his words (言) determine (定) the command.
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