What is monzonite in geology ?

Monzonite : definition

Streckeisen diagrams (or QAPF diagrams) - Classification of plutonic and volcanic rocks
A monzonite is a grainy, leucocratic plutonic rock, similar to a calc-alkaline syenite, containing as much orthoclase as plagioclase (oligoclase, sometimes andesine or labrador), green hornblende, fairly abundant augite, titanite, apatite, zircon, and very little or no quartz.

Monzonites ensure the transition between syenites and diorites, and are known in transition zones within large magmatic massifs. Brittany kersantite is the lamprophyre variety of monzonite.