Anorak (noun)

1. A type of jacket with a hood, made of waterproof or windproof material, originally worn by the Inuit people and now popular as outdoor wear.
2. A person with a keen interest in a particular subject, often considered to be unfashionable or socially awkward.

Origin:

From the inuit word annoraq, meaning "parka".

Examples:

1. I brought an anorak, just in case it rains.
2. His anorak was made of Gore-Tex, a waterproof and breathable material.
3. He was an anorak for trains and spent all his free time studying railway history.
4. Anoraks were seen as unfashionable, but they are now popular among outdoor enthusiasts.
5. The anorak kept him warm and dry in the blizzard conditions.