"A chunk of flesh" ?? Can someone tell me what does chunk mean?

Like a big piece of flesh

getting all joy luck club in here (idk if you guys read this book but it's an asian book and there was a chapter where the daughter cut a chunk of her arm to feed her mother i forgot why)

Thank you for telling me... Wow, thats so creepy and disgusting Σ( ￣□￣||)

About the meaning, i mean