Contraction may refer to: Lanthanide contraction, the decrease in size of the ionic radius of lanthanide elements with their growing atomic number (series of Rare Earth Elements (REE) in the Mendeleev Table). Contraction (childbirth), a contraction during childbirth (basically referring to muscle contraction). Contraction (grammar), a shortened term formed by omitting the middle of a word or words. Syncope (phonetics), the loss or reduction of sounds within a word. Braille contraction, used… (More on Contraction)