fall back

definition: go back to bad behavior
example:
speech part: verb
synonyms: lapse
definition: retreat
example:
speech part: verb
synonyms: drop off
definition: move back and away from
example:
speech part: verb
synonyms:
definition: hang (back) or fall (behind) in movement, progress, development, etc.
example:
speech part: verb
synonyms: lag
definition: fall backwards and down
example:
speech part: verb
synonyms:
definition: have recourse to
example:
speech part: verb
synonyms: resort

How fall back is being used?