Adjective;
1. A ridiculously sexy person.
2. An absolutely amazing session of sex.
3. An exceptionally complex setup made for the purposes of having sex.
1. "That chick is so hot, she's sextravagant."
2. "Last night was sextravagant, babe."
3. "When I entered the room, I saw that he had lit candles, put on some really good mood music, and scattered real rose petals everywhere! It was so beautiful and sextravagant!"