Mindfulness can be described as "gentle effort to be continuously present with the experience". I read this somewhere and thought it beautifully described Mindfulness.
Jon Kabat-Zinn - renowned for Mindfulness practice and teaching - describes it as "paying attention in a particular way".
I've also noticed it described as "the intentional, accepting and non-judgemental focus of one's attention on the emotions, thoughts and sensations occurring in the present moment".
Meditation is "singal pointed focusness". So Meditation is a practice that can help us become consciously less busy in the mind. It is a technique that can encourage and develop concentration, clarity, emotional positivity, and a calm seeing of the true nature of things.
With regular meditation practice we can observe the unhelpful patterns and strategies of our minds and therefore we're then able to cultivate new and more positive behaviours and ways of being. So with focussed practice our minds can become more clear, peaceful and yet more positively energised. This can be quite transformative if you wish it to be.
So the way I see it is Meditation is a technique that can assist us be more Mindful, and Mindfulness is a technique that can assist us during Meditation - they are different from each other, but support each other.