A mathematical relationship that can define the degree of success of any female at various competitions, including job interviews, sporting/dance events, and, most prominently, debate tournaments.
The relationship holds that the amount of clothes one wears is inversely proportional to their success the event or competition.
A female can have Lex A or be described as "Lex A". An unattractive female who tries to Lex A but does not receive its benefits still HAS Lex A, but risks embarrassment and social isolation.
See: sex appeal
Dude, that girl got a 28.5 round 4.
Yeah, only because she's got Lex A.