A touchdown vulture is a football player, specifically a runningback/fullback that comes in the game inside the 5 yardline in goalline situations and steals undeserved touchdowns. In most cases smaller better running backs do all the work between the 20's and these vultures (larger/worse backs) come in and fall down for 1 or 2 yards scoring the touchdown, killing the fantasy value of the much better skillful backs. Key examples are Mike Alstott or the modern day Lendale White.
Fantasy Owner #1 - Hey Chris Johnson just got a 30 yard run down inside the 5
Fantasy Owner #2 - Shit now that fat ass touchdown vulture LenDale is going to come in and get the score