Algal

any of numerous groups of chlorophyll-containing, mainly aquatic eukaryotic organisms ranging from microscopic single-celled forms to multicellular forms 100 feet (30 meters) or more long, distinguished from plants by the absence of true roots, stems, and leaves and by a lack of nonreproductive cells in the reproductive structures: cl-ssified into the six phyla euglenophyta, crysophyta, pyrrophyta, chlorophyta, phaeophyta, and rhodophyta.
contemporary examples

earlier this month, toledo, ohio, watched its munic-p-l water supply descend into an undrinkable stew of algal toxins.
are water filters b.s.? michael schulson august 18, 2014

historical examples

the algal host cells lie in the medulla, just below the upper cortex.
ohio biological survey, bull. 10, vol. 11, no. 6 bruce fink and leafy j. corrington

the algal hosts are usually dactylococcus or polycoccus, and both hosts are sometimes found in the same thallus.
ohio biological survey, bull. 10, vol. 11, no. 6 bruce fink and leafy j. corrington

the chains of cells are usually badly broken up, and the nature of the algal host is, therefore, difficult to distinguish.
ohio biological survey, bull. 10, vol. 11, no. 6 bruce fink and leafy j. corrington

the work was begun with an inquiry into the extent of the trouble from algal pollution.
the home medical library, volume v (of vi) various

it was, therefore, most desirable to devise a method of ridding the bed of algal growth without injuring the cress.
the home medical library, volume v (of vi) various

this only killed the algal growth with which the particles of copper came in contact and left the main body of alg unaffected.
the home medical library, volume v (of vi) various

the protoplasmic contents of this siliceous box-like unicell are very similar to the contents of many other algal cells.
encyclopaedia britannica, 11th edition, volume 8, slice 4 various

plural noun (sing) alga (ˈælɡə)
unicellular or multicellular organisms formerly cl-ssified as plants, occurring in fresh or salt water or moist ground, that have chlorophyll and other pigments but lack true stems, roots, and leaves. algae, which are now regarded as protoctists, include the seaweeds, diatoms, and spirogyra
adj.

1846, see alga + -al (1).
n.

(plural), 1794, from alga (singular), 1550s, from latin alga “seaweed,” of uncertain origin, perhaps from a pie root meaning “to putrefy, rot.”

algae al·gae (āl’jē)
pl.n.
any of various chiefly aquatic, eukaryotic, photosynthetic organisms, ranging in size from single-celled forms to the giant kelp.
algae [(al-jee)]

primitive organisms that contain chlorophyll but do not have structures, such as xylem and phloem, to transport fluids. algae sometimes contain only a single cell, and nowadays they are not considered members of the plant kingdom.

note: the most familiar algae are the greenish sc-m that collects in still water.

note: algae supply a considerable part of the world’s oxygen.