Mine is Omentum.

I went to med school for a grand total of one semester before I realized it wasn’t for me. But during that semester I went through Gross Anatomy in which you dissect a cadaver bit by bit over the course of (IIRC) 8 weeks. Anyway in the abdominal cavity lies the greater omentum, a yellow net-like contraption that basically spans the stomach & intestines. It’s super cool looking, probably my favorite structure I encountered in gross anatomy.

My least favorite thing about gross anatomy - other than that one really stinky cadaver - was Netter. Oh my god I felt like that text became an extension of my body, I was never not buried in it, along with so many lists of mnemonics. I still remember the mnemonic Roman Togas Don’t Cover Balls to name the parts of the brachial plexus (Roots, Trunks, Divisions, Cords, and Branches).