adjective

1. of, or having the form of, an island
2. living or situated on an island
3. like an island; detached; isolated
4. of, like, or characteristic of islanders, esp. when regarded as narrow-minded, illiberal, or provincial
5. Med.
   1. characterized by isolated spots
   2. of the islets of Langerhans or other islands of tissue

Etymology: L insularis < insula, island: see isle