pro·hor·mone 
(prō-hôrmōn′)
(prō-hôrmōn′)n.
An inactive compound that is converted by enzymes into a biologically active hormone.
- unpleasantry
- unplug
- unplugged
- unplumbed
- unpolished
- unpolitical
- unpopular
- unpopularity
- unpracticed
- unprecedented
- unprecedentedly
- unpredictability
- unpredictable
- unpredictably
- unprejudiced
- unpremeditated
- unprepared
- unpreparedly
- unpreparedness
- unprepossessing
- unpretending
- unpretentious
- unpretentiously
- unpretentiousness
- unpriced