Noun – “the company’s customer manufacturing department.”
Philip Kotler, Marketing Insights from A to Z, Page xi

Noun – “the company’s customer manufacturing and retention department.”
Paraphrased by Glyn Davies – Resultant

Verb – “Marketing is not the art of finding clever ways to dispose of what you make. Marketing is the art of creating genuine customer value. It is the art of helping your customers become better off. The marketer’s watchwords are quality, service, and value”
Philip Kotler, Marketing Insights from A to Z, Page xii

Think of marketing as creating an awareness of the genuine value of your solution, such that you could imagine that you have created a form of magnetism that naturally attracts customers to you, meaning that you don’t have to go out and pitch and sell.

The aim of marketing is to make selling superfluous.
Peter Drucker

Here’s a simple, jargon-free, definition of marketing:
If the circus is coming to town and you paint and display a sign saying ‘Circus Coming to the Showground Saturday’, that’s advertising.
If you put the sign on the back of an elephant and walk it into town, that’s promotion.
If the elephant walks through the mayor’s flower bed and the local newspaper writes a story about it, that’s publicity.
And if you get the mayor to laugh about it, that’s public relations.
If the town’s citizens go to the circus, you show them the many entertainment booths, explain how much fun they’ll have spending money at the booths, answer their questions and ultimately, they spend a lot at the circus, that’s sales.
And if you planned the whole thing, that’s marketing.