Ornithopter -> RC helicopter -> Quad[copter] -> Multi-rotor -> Drone ... which can be a $50 toy, a $5,000 photography machine, or $50 Million killing machine.

Ornithopter -> RC helicopter -> Quad[copter] -> Multi-rotor -> Drone ... which can be a $50 toy, a $5,000 photography machine, or $50 Million killing machine. bicycle -> cycle -> bike ... which can be a motorcycle too. Seems the trend is toward simple mono-syllabic words with high ambiguity in their meaning. Predict we end up with 'bot' when they are a part of everyday life.