Inhospitable describes a place that makes it extremely difficult or uncomfortable for people (or other living things) to survive or feel welcome. The Sahara Desert is inhospitable because of its scorching heat and lack of water. Antarctica is inhospitable because of its brutal cold and howling winds. The surface of the moon is completely inhospitable to human life, with no air to breathe and temperatures that swing wildly from boiling to freezing.

A hospitable person makes guests feel comfortable and at home. An inhospitable environment does the opposite: it threatens or challenges anyone trying to exist there.

You might hear someone describe a rocky mountainside as inhospitable terrain, meaning it's harsh and dangerous to cross. Ocean depths are inhospitable to humans without special equipment. Even a neighborhood could be called inhospitable if it feels unwelcoming or unsafe, though this usage is less common.

Despite being inhospitable, some of Earth's harshest places still support life. Penguins thrive in Antarctica's inhospitable climate, and camels survive in inhospitable deserts. These creatures have adapted to conditions that would quickly overwhelm humans. When explorers venture into inhospitable regions, they need extensive preparation, special equipment, and respect for the environment’s power.