1. -ward vs. -wards: In American English, the preferred suffix is -ward—for example, westward, forward, backward, downward. But because the -wards suffix is common, nobody will fault you for using it.
The -ward suffix may be placed at the end of any noun. There’s no need for a hyphen. Spell-checkers may catch words like cityward, mountainward, oceanward, or workward, but that shouldn’t stop you from using them.
2. Adjectives and adverbs: Directional words can be both adjectives and adverbs. No -ly is needed. Here are examples of both types used correctly:
The backward spin of a number of black holes could create mysterious jets of plasma that control the fate of galaxies . . . [MSNBC]
Financial markets gyrated downward again Friday as investors turned skittish on banks . . . [Wall Street Journal]
3. Capitalization of north, south, west, and east: When used as nouns denoting specific regions, these words should be capitalized—for example:
Threats of snow are shuttering schools across the South . . .
Abbas, who is traveling in the Far East and is due back in the West Bank on Monday, has not commented.
Their adjective forms, unless parts of proper names (e.g. West Virginia, South Australia, West Bank) should not be capitalized:
The birds are usually found in Iceland, Greenland, western Russia and Canada.
Much of the northeastern United States is battling deep snows and blizzard conditions Wednesday . . . [VOA News]
4. Northerly, southerly, westerly, easterly: In many cases, constructions involving these adjectives can be shortened to one word—for example:
The vessel was reportedly heading in a northerly direction.
This sentence could be shortened to,
The vessel was reportedly heading north.
These -ly words are most applicable when something moves gradually in a general direction—for example:
. . . El Nino conditions in the Pacific Ocean have helped create the persistent, southerly storm track this winter . . .
