The attraction to someone who is mature in years, older that the one obsessing over them. An arousal only for those considered to be adults.
From the Greek word "teleios" meaning 'full grown'.
Today's term was coined by a sexologist, Ray Blanchard.
Basically this applies to a sexual or erotic attraction to those who are adults, who are older than the one having the attraction.
Mainly it is for younger adults, having a sexual attraction for older adults, however, it can apply to minors who have an attraction for adults, instead of those within their own peer group.
In short, it is the erotic and sexual attraction by a younger person for a much older person, who is well outside their normal peer group.
Mainly used a means of comparison of age attractions.
Was also referred to as "adultophilia"