Kelp vs. Seaweed — What's the Difference?

Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera.

Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of Rhodophyta (red), Phaeophyta (brown) and Chlorophyta (green) macroalgae.

Any of various brown seaweeds of the order Laminariales, often growing very large and forming dense beds.

Large algae growing in the sea or on rocks below the high-water mark

The ashes of seaweed, formerly used as a source of potash and iodine.

Any of numerous marine algae, such as a kelp, rockweed, or gulfweed.

Any of several large brown algae seaweeds (order Laminariales).

A mass of such algae.

The calcined ashes of seaweed, formerly used in glass and iodine manufacture.

Any of numerous marine plants and algae, such as a kelp.

(intransitive) To gather kelp.

(by extension) Any of various fresh water plants and algae.

The calcined ashes of seaweed, - formerly much used in the manufacture of glass, now used in the manufacture of iodine.

Popularly, any plant or plants growing in the sea.

Any large blackish seaweed.

Any marine plant of the class Algæ, as kelp, dulse, Fucus, Ulva, etc.

Large brown seaweeds having fluted leathery fronds

Plant growing in the sea, especially marine algae