" He means this definition:
An assumption based on limited information or knowledge; a conjecture. "
Yes, the last one. You don't get to pick and choose which definition to use; their uses have already been established. A scientific theory is:
"A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena."
It is not "An assumption based on limited information or knowledge; a conjecture.".
You cannot make a horse from a fish...
Nor can you get a human from an ape
But, if you catagorize evolution to the developement of adapting to the environment, hence the theory of the giraffe getting a longer neck to reach the leaves higher in the trees..(bunk theory, why haven't all leaf eating animals developed long necks for survival?)
Most evolutionists want to believe life came from one cell. Creationalist believe in all creation developed by design.
I personally do not care, Something still had to start the whole process somewhere. You can't get something from nothing. Only life can beget life.