Bains defines meaning as
...genuinely listening to what people want and responding to it authentically, and one of the most important tools for driving business results in this century...People experience meaningfulness when they feel worthwhile, useful, and valuable; as though they made a difference and were not taken for granted. They feel able to give to others and to the work itself in their roles. Lack of meaningfulness is connected to people's feeling that little was asked or expected of their selves and that there was little room for them to give or receive in work role performances.
The critical thing for employers to understand here is that for people to be fully engaged they have to be able to see a return on for their personal investment at work