Hello and welcome aboard. It depends on what device you have; however, here is a step that works with any device: open up 'google play' (market app), then tap menu on your device hardkey and tap "my apps," then find the app in question tap on it and follow steps to uninstall.
Note: keep in mind that some apps cannot be uninstalled.
I hope this helps.
Also, check in to your device's area of support for some tips & tricks on your device.