con ‧ duc ‧ tor /kənˈdʌktə $ -ər/ BrE AmE noun [countable]
1 . someone who stands in front of a group of musicians or singers and directs their playing or singing
2 . British English someone whose job is to collect payments from passengers on a bus
3 . American English someone who is in charge of a train and collects payments from passengers or checks their tickets SYN guard British English
4 . something that allows electricity or heat to travel along it or through it:
Wood is a poor conductor of heat.
⇨ ↑ lightning conductor