I need a different word than this. It's got too many connotations in porn and I don't want that. I'm using it to describe a crayfish. "Inside the cage a couple mudbugs flopped around. They were about the size of his hand and had two long pincers outstretched from a girthy thorax. Its tail was short and segmented and flared out at the end. "
Let me thesaurus that for you... is girthy even a word? Girth is a type of.. size or something like circular or round. You wouldn't say squarey or spherey. Just change it to large, wide, or something similar.
Hmmm... Ok. But that would not be my choice. Plump brings to mind things that are squishy and soft. Babies are plump. Sausages are plump. JMO, though.