Other forms: fleshier; fleshiest; fleshily
Something that's fleshy is plump and thick, like the fleshy fruit of a ripe peach or the fleshy leaves of your giant rubber plant.
When it's not describing the soft, almost meaty tissue of a plant, the adjective fleshy is most often used for people who are plump or well-padded. While today the word tends to be somewhat derogatory and judgmental, the original meaning of fleshy was simply "consisting of muscle and flesh."