Get ready to slap your palm into your forehead: these ones are groaners. Like the double-meaning variety, the clues are very short and contain only the definition ("front door") portion of the clue. Homophones are words that sound the same but are spelled differently. Unlike anagram and composed clues, homophone clues are quite rare. Any given cryptic crossword puzzle will probably only have one or two, or might have none.
How Can You Tell if It's a Homophone?
Look for the trigger word
Unlike double-meaning riddles, homophone riddles have a trigger word that makes reference to the sound of the word. Common trigger words are: “overheard,” “spoken,” “verbal,” “oral,” and “described”. There might also be something like “I hear” or “auditor’s”, or even something very tricky like “over the radio” or “on the record”.
The answer to this clue is a word that, when spoken, sounds like a word that means "reference" and also like a word that means "point". Can you think of one? If you make reference to a particular text, you "cite" it. A geographical point is a "site".
How do you know which spelling to use?
The easiest way might be to look at the number of letters in the answer. But if both spellings have the same number of letters, you can confirm by looking at the clue. The meaning that comes after the trigger word, or is the closest to it, is the phonetic one (and therefore not the answer). So if you have “Auditor’s reference point”, the correct spelling is the one that relates to the "point"; the "reference" is the “auditor’s” spelling, which means it is the phonetic spelling.