According to Wikipedia, there's no precedent but --
"There is no male equivalent to a queen mother (i.e. "king father"). This would occur only if the husband of a queen regnant outlived the queen and was thereafter father to the new king or queen. Such a situation has never occurred. Since the title "queen mother" derives from the woman's previous title of "queen", it would also be incongruous to call such a father of a monarch the "king father", as the husbands of queens regnant are not given the title "king", but rather titled as a prince. The exact title such a person would assume has not been clarified by royal lineage experts. "Prince father" is a possibility."
Philip was never king. I kinda assumed 'queen mother' was like 'mother of the queen' but it seems its more 'mother who was the queen'.