Ious is defined as having or being like the word it follows.
(suffix)An example of the –ious suffix is the word luxurious.
See -ious in Webster's New World College Dictionary
Origin: < -i-, thematic vowel or stem ending + -ous, for Fr -ieux & L -ius
See -ious in American Heritage Dictionary 4
Origin:
Origin: Middle English
Origin: , partly from Latin -ius
Origin: and partly from Old French -ieus, -ieux (from Latin -iōsus)
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