q.d. (qd or QD) is once a day; q.d. stands for “quaque die” (which means, in Latin, once a day).
b.i.d. (bid or BID) is twice a day; b.i.d. stands for “bis in die” (which means twice a day).
t.i.d. (or tid or TID) is three times a day ; t.i.d. stands for “ter in die” (in Latin, 3 times a day).
q.i.d. (or qid or QID) is four times a day; q.i.d. stands for “quater in die” (in Latin, 4 times a day).
- Quaque die (on prescription)
If a medicine is to be taken every so-many hours, it is written “q_h”; the “q” standing for “quaque” and the “h” indicating the number of hours. So, for example, “2 caps q4h” means “Take 2 capsules every 4 hours.”
A period of isolation decreed to control the spread of infectious disease. Before the era of antibiotics and other medications, quarantine was one of the few available means for halting the spread of infectious diseases.
Prefix meaning seemingly, as in quasidominant (seemingly dominant).
Describing a cell that seems to have the usual two full sets of 23 chromosomes, but does not. Many malignant cells are quasidiploid. Also called pseudodiploid.
Pattern of inheritance that seems due to a dominant trait but is in fact due to the mating of a person who has a recessive disorder (with two copies of a gene causing the disease) with someone who is an asymptomatic carrier (with one copy of the same gene but no symptoms).