in·ver·sion 
/ɪnˈvɚʒən/ noun
plural in·ver·sions /ɪnˈvɚʒən/ noun 1 formal : a change in the position, order, or relationship of things so that they are the opposite of what they had been [count] ▪ an inversion of the roles of parent and child [noncount] ▪ Inversion of the two words changes the meaning of the sentence. 2 [count, noncount] weather : a condition in which air close to the ground is cooler than the air above it
▪ (a) temperature inversion
▪ (a) temperature inversion
