pack ice 
noun [mass noun]
A mass of ice floating in the sea, formed by smaller pieces freezing together.By contrast with pack ice, ice floes in the Chukchi Sea flaw zone move independently....
- In two years, observed densities on pack ice were much greater than those on fast ice; in the other two years, the densities on pack ice and fast ice were similar.
- There are two kinds of sea ice in Antarctica: fast ice and pack ice.
- peritonsillitis
- peritracheal
- peri-track
- peritrema
- peritrematic
- peritreme
- peritrich
- peritrichous
- peritrichously
- peritrope
- peritrophic
- peritus
- perityphlitic
- perityphlitis
- periungual
- periuranium
- peri-urban
- periureteric
- periurethral
- periurethritis
- periuterine
- perivascular
- perivasculitis
- perivenous
- periventricular