Looks like the abdomen burst?
Approximate size: 3/4 inch
Hi, welcome to Spider ID. 🙂 I’m not sure what happened to the abdomen, it’s possible it’s been dead a long time and it just dried out. Anyway, you have the remains of a Barn Funnel Weaver (Tegenaria domestica).
You rock. This spider may have spent some time in a freezer, which I think could have sped up the decomposition of the abdomen.