Pleonasm
Pleonasm, a type of tautology, is the redundancy in linguistic expressions such as "black darkness" or "burning fire" which already imply one part of the expression by the other. Giants are already, by definition, big. Pleonasm can be a literary device to give emphasis or dramatic effect, sometimes reflects established usage such as "safe haven", or can simply be an excess. Laconic refers to extreme brevity; an oxymoron is an apparent contradiction in terms (however, there is nothing inherently unfriendly about a giant); an aphorism is a pithy statement of a general truth.