In music, the fourth mode of the major scale, with the following half step/whole step progression: W-W-W-H-W-W-H.
Simliar to the major scale, except that it contains an augmented fourth, which turns out to be the tritone.
For example:
  • C Lydian contains the notes C D E F# G A B
  • Bb Lydian contains the notes Bb C D E F G A
  • E Lydian contains the notes E F# G# A# B C# D# E#
Two ways of playing the G Lydian scale in guitar tablature form:
Three notes per string:
e|--------------------------------5-7-9-|
B|--------------------------5-7-8-------|
G|--------------------4-6-7-------------|
D|--------------4-5-7-------------------|
A|--------4-5-7-------------------------|
E|--3-5-7-------------------------------|

Staying in the same neck position:
e|----------------------------2-3-5-----|
B|----------------------2-3-5-----------|
G|------------------2-4-----------------|
D|------------2-4-5---------------------|
A|------2-4-5---------------------------|
E|--3-5---------------------------------|