(sports, skateboarding, snowboarding, skiing) Clipping of 540. (540° spin)

That end of any DNA strand that has a terminal phosphate group.

(military) The planning section of an Air Force staff. / (military) Vigilante supersonic attack aircraft.

(informal) Relatively close to the 5′ end of a strand of DNA.

(US, slang, street slang) The police.

A day job, especially at a large company, emphasizing banality. / The workday itself (the period of the day between 9 am and 5 pm). / One who works in a job from 9 am to 5 pm.

Luxurious and expensive.

The neurotransmitter serotonin.

(psychology) The 2013 revision of the Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychiatric Association.

(music) A meter of five quarter notes per measure.