Which word best describes the act of triggering or intensifying desire?

The word that best describes the act of triggering or intensifying desire is "whet." This term is often used in contexts where someone's appetite or interest is heightened. For example, when a person "whets" their appetite, it means they are making themselves more eager or hungry for food. Similarly, in broader contexts, whetting desire involves creating or increasing interest, excitement, or craving for something.

In contrast, the other terms convey more negative connotations or involve the reduction of desire. "Quench" refers to satisfying or extinguishing a desire or need; thus, it diminishes rather than intensifies it. "Suppress" and "stifle" both imply inhibiting or holding back feelings or desires, leading to an opposite effect of the amplification intended by the question. Therefore, "whet" is the most suitable choice for conveying the idea of stimulating or heightening desire.