I hadn't really figured out my direction yet being in the early preliminary stages of the project, so I just went with what I thought propel meant. They're small thumbnails, and I know they're pretty rough, but they really helped me visualize my ideas more clearly, speeding up the cut and paste project.
The word 'propeller' kept popping into my head when I thought about my word. So I thought, 'hey, why not give it a shot?' So I googled 'propeller' and sketched up some basic airplane propellers.
I also kept associating 'fling' with this word (look at the sketches on the left-hand side). My mind kept going back to my grade school days. A food fight was started when Ryan Smith took his plastic spoon, his canned peas, and devious mind and catapulted his lunch across the cafeteria. I watched the whole thing go down: the tiny green ball leaving spoon, arching over Mrs. Wagner's class onto the supervisor's clipboard. What came afterwards is quite the story, but not important in this context. What IS important is how that tiny little pea took off from the spring of the spoon. It was 'propelled' into the air. So I took that little memory of mine and propelled my word into my composition.
I also googled trajectory, being that I kept associating that with propel too. It brought me back with a whole lot of physics jargon I didn't understand. But the graphs that these physics dudes made up were really pertinent to the idea I was going for, so I went with it (Mr. Bruecken, my high school general physics teacher would be proud).