A person who was born on the same day of the year as you. A truecosmictwin was born on the same day and same year as you (aka a Sense8), but colloquially any year is permissible.
Of the past 5 dates I’ve been on, two of them have been cosmic twins. I guess that means astrology is wrong, since opposites attract.
An intelligent person who is capable of doing math but, for reasons of entropy/fate/providence/bad luck, gets the answers wrong anyway, even to the extent that even math teachers are stumped as to why.
"I checked my answer 20 times. 20 TIMES! And the teacher checked it five times! I showed my work twice over. Neither of us knows how I got question 4 so wrong."
"You poor cosmic miscalculite..."