Let me help you......
1. Dominant---the fifth degree of a major or minor scale, often expressed as the Roman numeral V or v.
2. Sub-dominant--the fourth degree of a major or minor scale, often expressed as the Roman numeral IV or iv.
3. Augmented--this means on any interval, you raise or lower either the top note of the interval or the bottom note of an interval one semitone (or one half step). For instance, on a typical perfect 4th, with the notes A-D, if you raise the note D one semitone to D#, hence making the interval A-D#, you have created an augmented 4th. In chord symbols, augmented is often abbreviated "+" or "aug", or sometimes, "A" (for example, "A5"--augmented fifth, or "G7+5"--a G7 chord with the fifth in the chord augmented)
4. Suspension--this is usually a nonharmonic tone on a dominant (or V chord) that resolves to a harmonic tone. Take the chord G-C-D, which is the V of C major.
The "C" is the suspension. Now resolve the "C" by lowering it one semitone while keeping the other notes (G, D) intact. The result is the note "B", which is the resolution..hence making a G chord (G-B-D).
In chord symbols, "suspension" is abbreviated "sus" (e.g, Bbsus)
5. Pedal note....often this is called a pedal point or organ point. You see this a lot in the music of Bach. This means that the note is held through constant chordal changes. (Listen to the opening of the Saint-Saens piano concerto in G minor, where in the solo piano part, you hear the pedal note, G, in the bass over changing chords...a great music example).
6. Dissonance....Anything that makes the music discordant, or the state of music being discordant. Generally, the term refers to the nonharmonic tones of a chord, but can mean any note or chord, or any tone row or motif or melody that makes the music generally displeasing or not understandable to the music listener.
I also anticipate that you have other terms you are worried about...the submediant, the mediant, the leading tone, and the supertonic....
Here are all of the meanings...
7. Submediant---the sixth degree of the major or minor scale, often expressed in the Roman numeral VI or vi.
8. Mediant--the third degree of the major or minor scale, often expressed in the Roman numeral III or iii.
9. Supertonic--the second degree of the major or minor scale, often expressed in the Roman numeral II or ii.
10. Leading tone--the seventh degree of the major or minor scale, often expressed in the Roman numeral VII or vii.
I hope all of this helps you understand some of this difficult music
theory....