Trail left by a jet

VAPOR

["Here’s a helpful hint for the clue \"Trail left by a jet\":\n\n**\"Gaseous form of water seen in the sky.\"**\n\nThis hint guides the solver toward the concept of water in a gaseous state (vapor) without directly repeating the original clue or giving away the answer. It’s easier than the original clue but still requires a small leap of reasoning."]

The clue **"Trail left by a jet"** leads to the answer **"VAPOR"** through the following reasoning: 1. **Literal Meaning**: A jet aircraft often leaves behind a visible trail in the sky, commonly known as a **contrail** (condensation trail). This trail is formed by the condensation of water vapor from the jet's exhaust. 2. **Wordplay**: The word **"vapor"** directly refers to the gaseous state of water, which is a key component of the trail left by a jet. While "contrail" is the more specific term, "vapor" succinctly captures the essence of what forms the trail. 3. **Simplicity & Fit**: The answer is a short, concise word that fits the clue without unnecessary complexity, making it a likely choice in a crossword puzzle where brevity is often preferred. Thus, **"VAPOR"** is the correct answer because it describes the primary substance (water vapor) that makes up the trail left by a jet.