A line cliche is a singe line which moves through a single chord. The line cliche will always move chromatically:

The above line chliche can be identified as the single line:

While the basic chord remains:

Line cliches are very common in minor key harmonies.

Other characteristics of line cliches are:

1. They may occur on the top; in the middle; or, if the line cliche starts on the root of the chord (as the above line cliche does), on the bottom of the voicings. 2. They are used as guide tone lines and as lines developed in the voice leading process. 3. They always appear in the area of the chord above the 5th and below the root.

Another of the most common line chliches is:

Line cliches do not always continue their motion in the same direction:

When a line cliche is present, the available tensions are those for the triad.

Other line cliches can be found by starting on 6, -7, or maj7 chord degrees and moving chromatically:

Though line cliches are fundamentally associated with minor tonalities, they may be seen in major key harmonies. Most often on the I or IV chords:

or on the ii or iv or vi chords. When the line cliche occurs on the ii chord, it often progresses to the V7 chord:

Less often the line cliche may appear on the iii chord.

References

"Harmony 2" by Barrie Nettles, Berklee College of Music, Boston, 1987, pages 40-42