What is Atheism?

[Kernel Sohcahtoa]

This is a little obscure and esoteric, but there is a scene from an early episode of Steptoe and Son in which Harold, the son, challenges Albert, his dad, to show him the shrapnel wounds he claims to have received in WW1 and which he often uses as an excuse to get out of any hard work. Albert keeps prevaricating, throwing out red herrings and threats of violence. Anything to avoid having to actually back up his claim. As a last resort he says "I've got medals in that drawer", as though it's incontrovertible proof.

Long story short, that's what I picture whenever we get logical acrobatics and other smokescreen tactics in place of the evidence for which we ask.

I see little point in continuing until people stop using the word 'evidence' in a way that begs the question, i.e. as something already proven. This, as opposed to something evident (obvious, apparent, plain) presented to support an assertion.

My apologies if I have come off as thick.  My posts have been aimed at trying to gain a better understanding of your perspective on matters of theism and atheism.  Could you please elaborate on the part quoted in bold above.  From a theistic perspective, what do you define as something that is 'evident' (obvious, apparent, plain) and can be presented to support an assertion?