When the dental arch or part of it is farther away from the FH plane; the deviation is termed as:

Vertical deviations with respect to the FH plane are: Attraction: When the dental arch or part of it is closer to the Frankfort horizontal plane, it is referred to as attraction. Abstraction: When the dental arch or a part of it is farther away from the Frankfort horizontal plane, it is referred to as abstraction. Ref: Textbook of orthodontics Gurkeerat Singh 2nd ed page no 169