1. slide guitar definition:
Slide guitar or bottleneck guitar is a particular method or technique for playing the guitar. Instead of altering the pitch of the strings in the normal manner (by pressing the string against frets), a slide is placed upon the string to vary its vibrating length, and pitch
2. steel guitar definition:
A Guitar with metal strings and played by sliding a metal bar over the fretted neck rather than fingertips pressing the strings.A method of playing slide guitar using a steel. Resonator guitars, including round necked varieties, are particularly suitable for this style, but other types are also used, usually with modified high actions, as well as instruments produced specifically for the purpose.