fear, envy, loquacious
讋 centers on a mix of intense emotional states: fear, envy, and being overly talkative. These meanings do not share one clear conceptual center, but they can be seen as reactions to a powerful presence—fear and envy arise from it, and loquaciousness may be a nervous response.
讋 combines 龍 (dragon) and 言 (words). The exact historical development is uncertain, but it likely relates to the idea of being overwhelmed by a dragon's presence, leading to fear, envy, or excessive speech.
A dragon (龍) looms above, and your words (言) become a jumble of fear, envy, and nervous chatter.
For ショウ, imagine a dragon's roar making you show fear: show -> ショウ, and you can't stop talking nervously.