The phrase "for spell" can be replaced by a variety of synonyms depending on the context. It could be replaced with words like "for a short time", "temporarily", or "momentarily". Alternatively, you could use phrases like "briefly" or "intermittently" to convey the same idea. Other synonyms for "for spell" include "periodically", "from time to time", "occasionally", or "sporadically". Regardless of which synonym you use, the meaning remains the same: for a limited duration, or without continuity. By using these alternatives, you can add variety to your writing and avoid repetition.