Alternate / Alternative
UsageAlternate is clearest for taking turns; alternative is clearest for another choice.
Alternate
Use when
You mean occurring by turns, or every other one.
Example
“The teams chair the meeting in alternate months.”
Alternative
Use when
You mean another available choice or option.
Example
“The paper proposes an alternative delivery model.”
Quick check
alternative weeks, an alternate approach
Usage note
Alternate is also established for a substitute or another choice, especially in American English. Use the distinction when ambiguity matters.