What exactly does "従兄妹" or "従兄妹同士" mean, does it translate to "cousin" or "cousins"?


I saw it used in a short story online but was confused on what it meant since
I wasn't sure and don't know enough. When I used translation software, it just
translated the part as "cousins". Here is the context in the written dialogue
used, "しかも従兄妹同士とは．．．". The context is an old man learning that a guy and girl
were cousins in the story.




従兄妹 is one of the kanji representations the word いとこ can take. Others include:
従兄/従妹/従弟/従姉/従兄弟/従姉弟/従姉妹. The two kanji words refer to one person whose kin
relationship to the person of reference is cousin, namely person A is a cousin
to person B. The three kanji words refer to 2 or more people being cousins (to
one another).

When you add the word 同士 the combined phrase has more of an emphasis on the
people involved being on equal footing, e.g. they are cousins (every member of
this group is a cousin to the rest.) Another example is 恋人同士. When you say
this you try to stress the fact that the two people are lovers and whatever
happens is between lovers. You didn't include enough context or even a
complete sentence in your question for us to explain to you the meaning.

