In probability theory and statistics, a sequence of independent Bernoulli trials with probability 1/2 of success on each trial is metaphorically called a<unk> .  One for which the probability is not 1/2 is called a biased or unfair<unk> .
Fair coin
Mosaic 
Blunt 
Piped link
Pedunculated
Outlier
Pantopaque
Wonder 