crusty
adj.adj. having a hard outer layer or being old and dry. In a casual way, it can also describe someone who is grumpy or something that is dirty and worn out.
adj. having or forming a hard outer layer or coating. By extension, describes a person who is irritable and old-fashioned, or an object that is unpleasantly dirty and stiff.
The fresh bread has a delicious crusty top.
He washed his crusty old boots after spending the entire afternoon working in the muddy garden.
The professor was known for his crusty exterior and sharp tongue, though students eventually realized his grumpiness masked a genuine dedication to their academic success.
From Middle English, equivalent to crust + -y.
Often used both literally for food and figuratively for personality traits or cleanliness.