-aceous, -acea, -aceae, -aceaen, -aceus

(Latin: a suffix; having the quality of, of the nature of, characterized by, belonging to, resembling)

There are hunderds of words that utilize the -aceous suffix which are not shown here; however, the following will present important examples.

A suffix that forms adjectives and is used with technical combinations, especially in biological terms: "pertaining or belonging to, of the nature of, or characterized by; to be full of, to possess abundantly". The suffix -acea usually denotes "orders and classes in zoology" while the suffix -aceae usually denotes "orders and families in botany" and -aceaen is used to denote members of "orders of the animal kingdom".

capillaceous
1. Resembling a hair.
2. Having many filaments that resemble a hair or thread.
caprifoliaceous (caprifoli) (adjective), more caprifoliaceous, most caprifoliaceous
1. Belonging to the Caprifoliaceae, the honeysuckle family of plants.
2. Relating to, or belonging to the Caprifoliaceae, a family of north temperate, and boreal regions, shrubs or small trees including honeysuckle, elderberry, and guelder-rose.
3. Etymology: from New Latin caprifoliaceae, from caprifolium type genus, from Medieval Latin: "honeysuckle", from Latin caper, "goat" + folium, "leaf".
carbonaceous
Pertaining to, containing, or composed of, carbon; like coal.
carboraceous
ceraceous
Waxen; like wax.
ceracious
Cetacea
Whales, dolphins, porpoises; order of marine mammals comprising two extant suborders, Odentoceta (toothed whales) and Mysticeta (baleen whales); body fusiform, forelimbs modified as flippers, hindlimbs absent, tail bearing lateral flukes; nares dorsal; eyes small, pinnae absent; skin essentially hairless with thick layer of subcutaneous fat for insulation.
cetacean
Any of various wholly aquatic placental mammals belonging to the order Cetacea, which includes the dolphins, porpoises, and whales. Their bodies are fish-shaped and adapted for swimming, with forelimbs in the form of paddlelike flippers. Functional hindlimbs are not seen. The long tail ends in two tranverse flukes, horizontally flattened tail used for locomotion. Hair is found only on the muzzle. There is a thick layer of fat (blubber) beneath the skin.
cetacean mammal
Large aquatic carnivorous mammal with fin-like forelimbs no hind limbs, including: whales; dolphins; porpoises; narwhals.
chloranthaceous
Belonging to the plant-family Chloranthaceæ.
cineraceous
columbaceous
A reference to pigeons.
conchylaceous
Of the nature of shells, shelly.
cretaceous
crustacean

Also see this closely related -eous suffix unit.