restriction

Here the word stops naming a process and names the rule itself, so it counts and readily goes plural. Restrictions are things a law can contain and a government can renew. Thomas Stephen, writing in 1835, describes Sir Robert Peel's 1819 bill continuing "the restrictions contained in several acts of parliament" on cash payments. Where the act of limiting takes of, this sense usually takes on, as in a restriction on water use.

A Latin word that reached English through French: Middle English restriccioun came from Anglo-Norman and Middle French restriction, and they from Late Latin restrictiō, built on Latin restringō. Today it reads simply as restrict plus -ion. Like other action nouns, it is usually followed by of to name what is being held in, as in restriction of imports.

A microbiologist's term for a bacterial defense: endonucleases recognize particular sequences in incoming foreign DNA and cut it, while methylation at those same sites protects the cell's own genome. Scientific prose also uses the word in its everyday meaning. Phylogeny of Kinorhyncha Based on Morphology and Two Molecular Loci (2015) speaks of "restriction of lateral accessory spines to females", so only context signals the technical sense.