IPA: /ləˈsɪv.i.əs/
KK: /læsˈsɪvɪəs/
Relating to or showing strong sexual desire or interest.
The lascivious behavior of the character in the movie shocked many viewers.
Lascivious → It is formed from 'lascivus' (from Latin, meaning wanton or lewd) and the suffix '-ious' (meaning characterized by). The word 'lascivious' describes someone characterized by a desire for sexual pleasure or lewdness.
Think of someone who is 'characterized by' ('-ious') a 'wanton' desire ('lascivus') — that's why lascivious means having a lewd or sexual nature.