Narrowing may refer to:

• Narrowing (computer science), a type of algorithm for solving equations between symbolic expressions
  • Narrowing of algebraic value sets, a method for the elimination of values from a solution set which are inconsistent with the equations being solved
• Narrowing (historical linguistics), a type of semantic change
• Collisional narrowing of a spectral line due to collisions of the emitting species
• Motional narrowing of a resonant frequency due to the inhomogeneity of the system averaging out over time
• Perceptual narrowing, a process in brain development
• Q-based narrowing, a concept in pragmatics
• Stenosis, the narrowing of a blood vessel or other tubular organ