Question: is jos a word in scrabble?
Answer: JO is the only two letter-word containing J listed in the Official Scrabble Player's Dictionary (OSPD5) and Official Club and Tournament Word List (OCTWL or OWL/TWL), which is defined as "a sweetheart." Its plural is JOES, so don't try to stick an S on JO making JOS*; you will likely lose a turn.