• synonyms


  1. a long, narrow, thin strip of wood, metal, etc.; slat.
  2. a long, flexible strip of wood or the like, used in drawing curves.
  3. Machinery.
    1. any of a series of uniformly spaced ridges on a shaft, parallel to its axis and fitting inside corresponding grooves in the hub of a gear, etc., to transmit torque.
    2. feather key.
  4. Building Trades. a thin strip of material inserted into the edges of two boards, acoustic tiles, etc., to make a butt joint between them; a feather.
  5. Mathematics, Engineering. a function that has specified values at a finite number of points and consists of segments of polynomial functions joined smoothly at these points, enabling it to be used for approximation and interpolation of functions.
Show More
verb (used with object), splined, splin·ing. Machinery.
  1. to provide with a spline or key.
  2. to provide with a keyway.
Show More

Origin of spline

1750–60; orig. East Anglian dial.; perhaps akin to splint; compare Old English splin spindle
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for spline

Historical Examples

  • The clutch arm k slides upon a rod x, and has a feather projecting into a spline in x.

    Modern Machine-Shop Practice, Volumes I and II

    Joshua Rose

  • Fig. 1533 represents the chuck in use for holding a piece of shafting s to cut a keyway or spline in it.

  • The sliding half is driven by a feather fast in its bore, and sliding in a feather-way or spline in the shaft.

  • Grooves can be cut in both cleat and board and a tongue or spline inserted (Fig. 494).

    Woodworking for Beginners

    Charles Gardner Wheeler

  • Dowels can be used with this joint (see Dowelling), or grooves can be cut and a strip or spline or tongue inserted (Fig. 558).

    Woodworking for Beginners

    Charles Gardner Wheeler

British Dictionary definitions for spline


  1. any one of a series of narrow keys (external splines) formed longitudinally around the circumference of a shaft that fit into corresponding grooves (internal splines) in a mating part: used to prevent movement between two parts, esp in transmitting torque
  2. a long narrow strip of wood, metal, etc; slat
  3. a thin narrow strip made of wood, metal, or plastic fitted into a groove in the edge of a board, tile, etc, to connect it to another
Show More
  1. (tr) to provide (a shaft, part, etc) with splines
Show More

Word Origin

C18: East Anglian dialect; perhaps related to Old English splin spindle; see splint
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for spline


"long, thin piece of wood or metal," 1756, from East Anglian dialect, perhaps from older Danish splind or North Frisian splinj.

Show More
Online Etymology Dictionary, © 2010 Douglas Harper