The -Ous Suffix

I’ve spent a few days searching for a definition of the adjective suffix -ous. One would think, given the thousands of English grammar and language sites on-line, that finding such a definition would be simple. One would be mistaken. I found many sites that purport to list suffixes and their respective meanings, but nary a one included a -us or -ous ending. Thus, I’ve begun a list of such words and an inexact definition of each.

I aim, here, to find a meaning of the -ous suffix for adjectives. Thus, the following “definitions” focus on what that suffix adds to the root word rather than the meaning of the word as a whole. As a rule, dictionary and etymology resources cite Latin origins for these words ending in -us. Then again, many Latin words share that ending and do not take an –ous suffix, so I can’t leap to the conclusion that those two circumstances are related.

If you know of anything that these words share in common in their respective histories, please let me know. You may see a theme emerging, below. If I find or learn more, especially a more widely-accepted definition, I’ll post again. Until that happens, my list stands as follows:

• tortuous (and circuitous) - in a complicated or round-about manner
• devious - in a deviant or devilish manner
• capricious - in the manner of caprice (a whim)
• joyous - in a joyful manner
• felicitous - in a happy manner
• delicious - in a delightful manner
• porous - having pores (in an open or penetrable manner)
• voluminous - having volume (in a large manner)