1. hide or disguise.   Hint First letter clue   2. surround or enclose.   First letter clue   3. cut with sharp-edged tool; cheat or treat unfairly.   First letter clue   4. encode a message.   First letter clue   5. make impure by mixing with baser ingredients.   First letter clue   6. slow down.   First letter clue   7. move faster or speed up.   First letter clue