-ous, -ious, -eous

(Latin: full of or having the qualities of; in chemistry, a suffix denoting that the element indicated by the name bearing it, has a valence lower than that denoted by the termination -ic; as, nitrous, sulphurous, etc., as contrasted with nitric, sulphuric, etc.)

Only a small number of the hundreds of examples are presented because there are just too many to include at this time.

seditious
sedulous
1. Diligent in application or pursuit; constant, steady, and persevering in business, or in endeavors to effect an object; steadily industrious; assiduous; as, the sedulous bee.
2. Persevering and constant in effort or application; assiduous.
3. Characterized by or accomplished with care and perseverance.
sensuous
1. Appealing to or enjoying the pleasures of sensation, other than those associated with sex.

Sensuous is distinguished from sensual by gratifying the senses for the sake of aesthetic pleasures or the delight in beauty of color, sound, or form that is induced while sensual tends to imply the gratification of the senses or the indulgence of the appetites (as of gluttony and lust) as an end in itself.

2. Greatly appreciative of the pleasures of sensations.

Sensuous usually means a powerful appeal to the senses or to the esthetic faculties; such as, the sensuous delicacy of a rose petal.

Sensual, on the other hand, refers more to some sexual application; such as, a sensual sculpture of a nude.

The difference between the two words was the original reason for creating the expression sensuous. The poet, John Milton, is said to have invented the word in order to have a synonym for sensual, minus the association with sex. He used the word in an often-quoted formulation of what poetry should be: "simple, sensuous, and passionate".

-A compilation of excerpts found in Family Word Finder; by editors of the Reader's Digest Association;
Pleasantville, New York; 1975; page 706.
serendipitous
1. To come upon or found by accident; fortuitous: "There have been many serendipitous discoveries in science."
2. A reference to, or suggesting serendipity.
3. Good; beneficial; favorable: "It was serendipitous weather for our trip to Italy."
serious
1. Grave in quality or manner.
2. Carried out in earnest: "He was engaged in serious drinking".
3. Deeply interested or involved: "She was a serious card player."
4. Designed for and addressing grave and earnest tastes; such as, serious art; serious music.
5. Not trifling or jesting: "We're serious. We expect you to complete the assignment on time."
6. Of considerable size or scope; substantial: "The city had a cleanup that cost serious money."
7. Of such character or quality as to appeal to the expert, the connoisseur, or the sophisticate: "Every serious kitchen needs at least one freezer."
8. Concerned with important rather than trivial matters.
9. Being of such importance so as to cause anxiety: "She had serious injuries."
10. Too complex to be easily answered or solved: "The governor raised some serious objections to the proposal."
11. In medicine, (of a patient's condition) having unstable or otherwise abnormal vital signs and other unfavorable indicators, as loss of appetite and poor mobility.
sonorous
soporous
1. Associated or affected with a coma or profound slumber; resembling sound sleep.
2. Soporific; sleep-bringing.
spacious
Offering or containing much space or room; extensive.
specious (adjective)
A reference to something that is right or plausible in appearance, but not necessarily the real thing.
spiriferous
Having a spiral structure.
spirituous
stentorious
A voice which is loud, powerful, or booming.
subconscious
1. In psychology, partially or imperfectly conscious; for example, belonging to a class of phenomena resembling those of consciousness but not clearly perceived or recognized.
2. Belonging to that portion of the mental area the processes of which are outside the range of attention.
3. The part of the mind that is not fully conscious but which is still able to influence actions, etc.
supercilious (soo" pur SIL i uhs)
1. Expressive of contempt: "He curled his lip in a supercilious smile."
2. Having or showing arrogant superiority to and disdain of those someone views as unworthy: "Her mother eyed my clothes with a supercilious attitude."
3. Disdainful or contemptuous; full of or characterized by pride or scorn.
4. Anyone who arches his/her eyebrows and looks down her/his nose at someone; in other words, "a high brow".
5. Etymology: from Latin with special reference to a facial expression with raised eyebrows; hence, pride, haughtiness; from super, "above" + cilium, "eyelid".

When someone raises his/her eyebrows, it doesn't necessarily mean she/he is disdainful, contemptuous, etc. Such action may also express surprise, curiosity, etc. Consider the context, or particular situation, before accusing someone of being supercilious.

superfluous
1. Being more than is sufficient or required; excessive.
2. Unnecessary or needless.
3. Possessing or spending more than enough or necessary; extravagant.