bol. means bolus - as a large single dose usually intravenously in Prescription
Similar to bol.
a.m. - ante meridiem - morning, before noon A.T.C. - around the clock a.u. - auris utraque - both ears aa - ana - of each ad - ad - up to ad lib. - ad libitum - use as much as one desires; freely admov. - admove - apply