vasopressor: any agent that produces vasoconstriction and a rise in blood pressure (usually understood as increased arterial pressure)
vasoconstrictor: any agent that causes a narrowing of an opening of a blood vessel: cold or stress or nicotine or epinephrine or norepinephrine or angiotensin or vasopressin or certain drugs; maintains or increases blood pressure
punctuation: the marks used to clarify meaning by indicating separation of words into sentences and clauses and phrases