1. (noun) a plumber.
2. (noun) industry slang for a lower-echelon upstart or novice plumber, often due to the nature of the majority of cheap, quick, service calls he/she commonly performs (id es, cabling out clogged pipes).
Journeyman Plumber: Boss, that property management company called back. Another gummed up garbage disposal...
Master Plumber: We're starting a full stack replacement and all new copper supply lines today--and it has to be done by next Tuesday. Let 'em call the turd-chasers. We're busy with real plumbing.