Dinoflagellate and Mastigophoran

Dinoflagellate noun - Chiefly marine protozoa having two flagella; a chief constituent of plankton.

Mastigophoran and dinoflagellate are semantically related. In some cases you can use "Mastigophoran" instead a noun "Dinoflagellate".

Mastigophoran noun - A usually nonphotosynthetic free-living protozoan with whiplike appendages; some are pathogens of humans and other animals.

Dinoflagellate and mastigophoran are semantically related. Sometimes you can replace term "Dinoflagellate" with "Mastigophoran", this nouns are similar.