mc-

   or mc¹

   alternate symbol for micro- (see below). This prefix is often seen in the symbol mcg for the microgram. The use of the symbol mc- for micro- became established because typewriters and early dot matrix printers did not have the proper symbol µ-. Also, many hospitals require the use of mc- in all handwritten notes and records, because a hastily written "µ" may be mistaken for an "m," leading to serious dosing errors. However, the use of mc- for micro- is also confusing and should be avoided as much as possible. One source of confusion is that mc- may be interpreted as "millicenti-", a mistake that could also lead to dangerous dosing errors. Occasionally, mc has been used as a symbol for the micron (see below).