Mornin' Charlann -
Tampa Stan gave a great definition of a lift.
I use a lift in the song I submitted for this week's Mentor Forum, Falling From Your Grace - the last line of the verses leading into the chorus vocally and musically rise, to build the energy to the chorus.... it's a clue that "something's comin'"

I believe sometimes the terms "lift" and "pre-chorus" are used interchangably. A pre-chorus sets up the chorus ... so does the lift, but the lift must do what it says ... So, I think a lift is a pre-chorus, but a pre-chorus may not always be a "lift".
I brought this song earlier to an NSAI critique and the over-all comment was my lift didn't lift musically ... I needed to re-write the music there to build into the chorus... I haven't been back to a critique since I made the change, so I am not 100% sure I accomplished my goal

... but that was the goal ...
It's on my soundclick page if you would like to take a listen.
http://www.soundclick.com/bands/pagemusic.cfm?bandID=100751Joanne