con·tra·dic·tion 
/ˌkɑ:ntrəˈdɪkʃən/ noun
plural con·tra·dic·tions /ˌkɑ:ntrəˈdɪkʃən/ noun 1 : the act of saying something that is opposite or very different in meaning to something else [count] ▪ No one was surprised by the defendant's contradiction of the plaintiff's accusations. ▪ Her rebuttal contained many contradictions to my arguments. [noncount] ▪ I think I can say without fear of contradiction [=I can say with absolute certainty] that this year has been very successful for our company. 2 : a difference or disagreement between two things which means that both cannot be true [count] ▪ There have been some contradictions in his statements. ▪ There is a contradiction between what he said yesterday and what he said today. [noncount] ▪ Her statements are mired in contradiction. ▪ What he said yesterday is in direct contradiction to what he said today.
contradiction in terms
: a phrase that contains words which have very different or opposite meanings
▪ I think “working vacation” is a contradiction in terms.
▪ I think “working vacation” is a contradiction in terms.
