The meaning of 120/80 mm of Hg blood pressure is that the person has normal blood pressure. 120 mm of Hg is the systolic pressure and 80 mm of Hg is the diastolic blood pressure.
Blood pressure categories
Normal: Blood pressure numbers of less than 120/80 mm Hg are considered within the normal range. If your results fall into this category, stick with heart-healthy habits like following a balanced diet and getting regular exercise.
Elevated Elevated blood pressure is when readings consistently range from 120-129 systolic and less than 80 mm Hg diastolic. People with elevated blood pressure are likely to develop high blood pressure unless steps are taken to control the condition.