an important and respected person in a group or organization.

A leading light in the art and ballet world, he was a close friend of Princess Diana. (often + in)

Jeffries, at 23 a leading light of the campaign, was the first to speak. (often + of)

• wheels are turning
• when all is said and done
• when back is turned
• when hell freezes over
• When in Rome .
• When in Rome do as the Romans do.
• when it comes to the crunch
• when push comes to shove
• when ship comes in
• when someone's back is turned
• when someone sneezes, someone catches a cold
• when someone sneezes, something catches a cold
• when someone was a mere twinkle in father's eye
• when someone was a mere twinkle in their father's eye
• when someone was a twinkle in father's eye
• when someone was a twinkle in their father's eye
• when something sneezes, someone catches a cold
• when something sneezes, something catches a cold
• When the cat's away .
• When the cat's away the mice will play.
• when the chips are down
• when the dust settles
• when the going gets rough
• when the going gets tough
• when the spirit moves