If something is streaky, it has streaks on it or is made of streaks.
Streaky things might make people think of messes or patterns.
Examples:
The streaky window was hard to see through.
Her painting was the streakiest of them all.
The cat's fur was streaky and soft.
The streaky banana was funny to look at.
The sky was the streakiest I had ever seen.
The ice cream was streaky and delicious.