A fellow contending with the adjectival content wrote us when he realized that making a connection between the adjective content meaning "feeling or manifesting satisfaction with one's possessions, status, or situation;" and the noun content, naming "something contained;" or "substance; gist, significance" might be a less contentious matter than expected. (来源：http://www.EnglishCN.com)

That’s because the noun content has an ancestor in the Latin word meaning to "hold together; hold in" (con means "with; together; jointly;" and tenere means "to hold"); and—no need to hold your breath—so does the adjective content. To us, it’s pretty satisfying to think that holding together equates with contentment.

Just as satisfying is the story behind contentious. While content and content come from the Latin contenere, contention comes from a different Latin word, contendere, meaning "to stretch vigorously; strive." Surely, vigorous stretching could be considered a sort of contentiousness, a perverse and often wearisome tendency to quarrels and disputes. Or at least, that is what we would contend.