From Longman Dictionary of Contemporary Englisha leading light in/of somethinga leading light in/of somethinginformalIMPORTANT someone who is important in a particular organization She’s one of the leading lights of the local dramatic society. → light
Examples from the Corpus
a leading light in/of something• On renouncing alcohol he was pardoned and he set sail for Darlington where he became a leading light in the Society.• Mrs. Shaewitz is a leading light in the local drama society.• She loves gym workouts, swimming and playing netball - she is a leading light in a local women's team.• By 1991, it was a leading light in outlandish front suspension concepts. 