Baretti: A dictionary of the English and Italian languages
Imboccáre, v. a.
1. to put food into the mouth;2. to prompt, to instruct or prepare one beforehand as to what is to be said or done; v. n. 1. to learn; 2. to discharge, empty itself (as a river). — col cucchiajo voto, to pretend to instruct but not to do so. — le artiglierie, to dismount the enemy's artillery; 3. to insert, join.
Florio: a worlde of wordes, or most copious, dictionarie in Italian and English
imboccare: to mouthe-in, to feede or cram, to put into ones mouth. Also to stop the mouth of a Cannon. Also to runne into some riuer or creeke of the land, as the Sea doeth in many places. Also for a Ship to enter the mouth of any riuer, as we say to embogue.