Northwest has 9 different meanings across 3 categories:
the northwestern region of the United States
"The tech startup decided to relocate its headquarters from California to the northwest region of the United States for lower operating costs."
the direction corresponding to the northwestward compass point
"The storm clouds gathered directly in the northwest, threatening to bring heavy rain to our town by evening."
the compass point midway between north and west; at 315 degrees
"The storm system is tracking directly from the northwest, bringing heavy rain to our coastal towns."
a location in the northwestern part of a country, region, or city
"The new branch office opened its doors last week in the northwest corner of Seattle to serve customers from the surrounding suburbs."
The compass point halfway between north and west, bearing 315°, abbreviated as NW.
"The storm system is currently moving through the northwest corner of the state before heading east."
In plain English: Northwest is the direction that lies between north and west on a compass.
"The ship sailed northwest across the open ocean."
Usage: Use "northwest" as a noun to refer specifically to the direction located halfway between north and west on a compass. It functions as a single unit of location rather than two separate directions when describing where something is situated or facing.
situated in or oriented toward the northwest
"The new shopping mall is located just a few miles northwest of downtown, making it easy to reach from the highway."
Of or pertaining to the northwest; northwestern.
"The house overlooks a stunning view of the rugged, tree-covered hills in the northwest part of the valley."
In plain English: Northwest describes something located toward both the north and west directions at the same time.
"The northwest corner of the room was painted blue."
Usage: Use "northwest" as an adjective only when referring specifically to the direction or region in the corner between north and west, such as in "the northwest wind." Do not use it as a general synonym for "northern" or "western," which have their own distinct adjectival forms.
to, toward, or in the northwest
"The plane began its descent as it approached the city from the northwest."
Northwest comes from Middle English and Old English, where it was formed by combining the words for "north" and "west." The term has retained its original meaning of describing the direction between those two cardinal points as it entered modern English.