1. the repeated occurrence of two different things in turns; successive change from one thing to another and back again
2. a single change from one thing to another

Examples

• The alternation of day and night creates our natural sleep cycle.
• There was a clear alternation between periods of rain and sunshine.
• The alternation of power between the two political parties continued for decades.
• The poem follows an alternation of long and short lines.
• We noticed an alternation in her mood throughout the day.
• The alternation between hot and cold weather made it difficult to dress appropriately.
• The alternation of colors in the pattern created a striking visual effect.