Smooth talk: comparing "sleek" and "streamlined"

What is similar?

Both "sleek" and "streamlined" describe something that is smooth, efficient, and potentially modern in design or function. They both convey a sense of elegance and refinement, often used to describe designs, shapes, or processes that are polished and free of unnecessary elements.

What is different?

The word "sleek" primarily emphasizes smoothness, elegance, and sometimes shininess, often with an aesthetic focus. "Streamlined" focuses more on efficiency, reduction of resistance, and optimization, often used in contexts related to design improvements for performance.

Which one is more common?