Saw my dead grandpa for a split second
Dreams about deceased loved ones are relatively common and can be interpreted as a manifestation of one's longing for that person or a desire for more time with them. In this case, seeing your dead grandpa for a split second in your dream could represent the longing you have for him or your desire to connect with him in some way. It may also suggest that you are still processing his passing and coming to terms with your grief. It's important to keep in mind that dreams are highly personal, so the true meaning of this dream may be subjective to the individual experiencing it.