7, 8, 9, 10
Each answer contains 7, 8, 9 or 10 letters. The following answer is made from the same letters, but by adding or subtracting one letter.
1. (10 letters) An area of tall, densely growing, broad-leaved evergreen trees in an area of high precipitation
 Rainforest
2. (-1) One of a row of sharp tooth-like projections found on a saw edge
 Serration
3. (-1) People authorised to perform acts in legal affairs, in particular witnessing signatures on documents
 Notaries
4. (+1) Male singers
 Baritones
5. (-1) A form of address used in Spanish speaking countries
 Senorita
6. (-1) A crime once punishable by death
 Treason
7. (+1) An ancient relative
 Ancestor
8. (+1) A prostitute or concubine with a wealthy, or upper-class clientele
 Courtesan
9. (+1) People who are skilled in relating amusing or witty stories and anecdotes
 Raconteurs
10. (-1) 16th century court dances, consisting of short advances and retreats
 Courantes