Streamlined vs Streamliner - What's the difference?

As an adjective streamlined

is designed to offer little resistance to the flow of fluid, especially by having sleek, graceful lines.

is (streamline).

something with a streamlined design, especially railroad locomotives and passenger equipment.

(en adjective)

Designed to offer little resistance to the flow of fluid, especially by having sleek, graceful lines.

Having been made more simple and straight forward.

(head)

(streamline)

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(en noun)

Something with a streamlined design, especially railroad locomotives and passenger equipment.