What's the difference between rigor and rigorousness?
Which should I use in the following?
Rigorousness and clarity are not synonymous in pedagogy.
Learn English – What’s the difference between “rigor” and “rigorousness”
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Related Solutions
A rock is bigger, possibly immovable, you couldn't throw it with one hand, at a pinch you might be able to with two.
Above, a Google Image result for "Rock", below, for "Stone"
Note that a boulder is probably bigger than a rock1.
Below, a boulder
Oh, also note that rocks and boulders are made from stone.
(This answer is mildly tongue in cheek)
1 Notable exception: Uluru/Ayre's Rock.
Cutlery has two definitions: 1. cutting/edged implements used for serving or eating food; 2. eating utensils in general. Without further context, an American is likely to assume the first definition (knives), while a Brit is more likely to go for the generic meaning. Silverware also means eating utensils, especially silver-colored ones, though nowadays, most silverware is not actually made of silver. An American synonym that does not imply anything about the silver content (or lack thereof) is flatware.
Crockery is completely different: in British English usage, it means the things on the dinner table that are usually made of china or porcelain -- plates, bowls, saucers, cups, serving bowls, etc. In American English, crockery is used for certain earthenware cooking pots, but given enough context, an American would probably understand crockery used according to the British definition.
Best Answer
The relationship between rigor and rigorousness is that rigor is similar in meaning to “severity” or “strictness”, but rigorousness is primarily “the abstract property of having to do with, or being inclined to, rigor”. As for which is best in your sentence, it simply comes down to which one you mean.
The suffixes -ous and -ness are productive, meaning they are used by English speakers as part of habits or “rules” for producing new words. These compound words, in the ears of English speakers, will generally mean what the individual parts mean.
The suffix -ous takes a noun X and creates an adjective X-ous which stands for “having X”, “full of X”, “having to do with X”, “doing X”, or “inclined to X”.¹
The suffix -ness can take an adjective Y and create a noun Y-ness which stands for the abstract action, quality, or state which Y has to do with.² You can think of this as converting a description of something to a property which it possesses.
As you might expect, then, when these productive suffixes are used together with a noun Z, the resulting compound Z-ous-ness will mean “the abstract action, quality or state of having/being full of/having to do with/doing/being inclined to Z”. You can think of this as converting a thing to an abstract property having to do with such a thing.
Because these habits or “rules” of new word production are instilled into the minds of English speakers, they will find it possible to make sense of words which are invented using this method, even when the combinations have never been seen before.
Such habits or “rules” are not, of course, the whole story. Once a new word is coined by compounding with suffixes and becomes a popular word, it is tossed and buffeted by the same social forces which cause all words to evolve in meaning. The compound may acquire unique connotations which do not wholly apply to its parts. A good dictionary will provide this information.