Both “Collosus” and “Colossus” are correct names for the tht2-drcs.  However, the formal name for the tht2-drcs is “Collosus.”  “Star Wars” aficionados will get the reference.  “”Colossus” is the informal name for the tht2-drcs, which semantically reflects the functional magnitude of the tht2-drcs.  Also, “Colossus” means something to computer historians.