useless trivia: What Word Means: An Alluvial Deposit?

Questions

- The section of a movement when initial statements of themes are expanded, developed, modified and broken up.?

- Adjective describing major and minor scales and also modes. The opposite of chromatic music which introduces notes not in the prevailing key. Diatonic harmonies, intervals, passages, etc. are made up of notes of the current key.?

- A triad in which the perfect fifth is reduced chromatically by a semitone (e.g. A C and E flat.?

(It.) - Gradually becoming softer. See decrescendo.?

- The treatment of a melody by shortening the time values of notes, usually by half (e.g. in fugues and canons).?