Lustrous hair belonging to the aggressive sub-species of sports players, homo sapiens laxus, more commonly known as "lacrosse players." Commonly known for their large physique, popped collars, and often womanizing behavior, these mammals typically have full, healthy manes, often envied by the other weaker members of the species, homo sapiens sapiens, aka normal dudes. One behavior associated with lax locks is the head toss, in which the hair is casually and smoothly flicked from the face.
Scrawny dude: Aw man, look at that guy's hair. It's so shiny and awesome looking.
Other dude: Bro, that's cause he's got lax locks. Only laxers
are lucky to get that kind of hair.