'Rashi' #1: It is an expression of multiple pieces [of its flesh]. When the fish is cooked, they appear to lie on each other. First Hashem discussed Livyasan's scales, then its pieces of flesh and strength of its heart.

'Rashi' #2: This is like Pil'ei Piluyei (Nidah 21) - they are cleaved.

Ibn Ezra: They are fatty places that hang on its flesh. This is like "u'Mapal ¹ Bar Nashbir."

Malbim: They are pieces of meat that fall from other living beings. In Livyasan, they stick to it like solid metal.

'Rashi': Every piece is solid with the others. Yatzuk is an expression of Mutzak. The conjugation is like what was done, like Yarud from Yarad, Yadu'a from Yada.

Refer to 41:15:1:4.