Whatever you call it, you're probably trying to choose just the right wick for your candle from the hundreds available. There are so many, it can be quite daunting. Yes, there are a lot of variables, but it's not rocket science - it's just candle science.
A Well Wicked Machine
Think of a candle as a solid chunk of fuel and the flame as a small engine that gives off heat and light. The wick is the pipeline that carries the fuel to the engine. When you light the candle, the wick burns and melts a bit of the solid fuel into a liquid. It then “wicks” this melted fuel to the flame, which burns the fuel. As with any pipeline between fuel and engine, you need the right size and/or type of pipe to work most efficiently. A range of sizes may work…but too small a pipeline will starve the flame or make it sputter. Too big a pipeline gives too much fuel to the flame making it burn too hot or drowning it altogether. Like Goldilocks finding the combination that is “just right”, you too can find the right size that is good for your combination of size, wax, fragrance and additives.