Preposition that can be represented by a number

FOR

Think of the homophone for this word that sounds like you're counting to four but is spelled differently.

The word "for" is a preposition, and the clue hints at its connection to the number 4—they sound identical. In crosswords, this kind of wordplay relies on homophones, where words that sound the same can stand in for each other. So "represented by a number" means the preposition shares the same pronunciation as the digit "four."