The rules for capitalization are both concrete and fluid. The rules are concrete because the style sheet always dictates how the capitalization must be handled in the manuscript and exceptions are not permitted. But the rules are fluid in that the CMOS and AP style guides and in-house style sheets for different publishers or businesses each set their own standards. Thus, you must know what your style guide requires and follow the rules consistently.
We are going to cover three major areas where capitalization rules are in effect:
- Common vs. Proper Nouns
- Titles
- Terms Associated with God
Common vs. Proper Nouns

Capitalization of common and proper nouns is generally handled the same way regardless of your style guide. So, let’s start by defining what we mean by a “common” noun and a “proper” noun.
Common Noun
Common nouns function as objects and are modified by an article or adjective.
Proper Noun
Proper nouns function as titles or proper names.
As one might guess, proper nouns ARE capitalized and common nouns are NOT. So, let’s look at some examples:
Each day, Mom prepares hot meals for her grandmother.
“Mom” is a proper noun identifying the title of the subject; it is NOT modified by an adjective or article. “Grandmother” is a common noun modified by the possessive adjective “her.”
Two of the most important presidents of The United States of America were President George Washington and President Abraham Lincoln.
When used as the office title with the person’s name, “President” is a proper noun. When functioning as an object, “president” is a common noun modified by “the most important.”
Also watch out for the use of “earth” vs. “Earth.” As with all names, the names of the planets are always capitalized. But in the case of the Earth, we also refer to the ground as “earth.” So, the simple rule is, if you are referring to the cosmic planetary body, “Earth” is capitalized. If you are referring to the soil or you are using expressions like “earth-shattering,” then “earth” is NOT capitalized.
After the comet crashed into the Earth, scientists sampled the earth around the crater to look for foreign contaminants.
NOTE: The article “the” before the proper noun “Earth” is sometimes omitted.
Jane loves vibrant neon colors, but Allison prefers the earth tones.
Titles

The CMOS and AP style guides have different rules for capitalizing words in a title, and these rules also vary when using sentence-style capitalization vs. headline-style capitalization. We will only cover the basics of headline-style capitalization here. Be sure to refer to your style guide for the complete set of rules.
CMOS
- Capitalize the first and last words.
- Capitalize all major words: nouns, pronouns, verbs, adjectives, adverbs.
- Capitalize all conjunctions except: and, but, for, or, and nor.
- Lowercase all prepositions.
- Lowercase “to” and “as.”
The Battle Dance: Courting under Pressure to Woo the World’s Most Exotic Birds While Outclassing or Eliminating the Challengers
The first “the” is capitalized because it’s the first word of the title; all remaining articles are lower case. The conjunction “while” is capitalized, but the conjunction “or” is not. The preposition “under” is lowercase.
AP
- Capitalize the first word.
- Capitalize all major words: nouns, pronouns, verbs, adjectives, adverbs.
- Capitalize all conjunctions of 4+ letters.
- Capitalize all prepositions.
The Battle Dance: Courting Under Pressure to Woo the World’s Most Exotic Birds While Outclassing or Eliminating the Challengers
In this example, the only difference between the AP and CMOS standards is the capitalization of “under.”
Following the rules above, if a hyphenated word is to be capitalized, there are additional rules for whether or not to capitalize the element following the hyphen. The AP Style Guide does not list rules for hyphenated words, but suggests that both elements be capitalized. Per CMOS, after the hyphen, make the following items lowercase and capitalize everything else:
- Articles
- Prepositions
- Conjunctions: and, but, for, or, and nor
- Modifiers following musical key symbols, e.g. –flat, –sharp
- Common nouns following a prefix (e.g. Pre-, Anti-) that is not a word by itself
Anti-war or Anti-Beulah: Record-Breaking Turnout at Peace Rally Puts CEO of Twenty-First-Century Tank Manufacturer in Its Crosshairs
“War” is a common noun following the prefix “anti-,” which cannot stand on its own as a word in its own right. “Beulah” is a proper name and must be capitalized even after “anti-.” “Record” and “Twenty-First” stand on their own, so “breaking” and “century” are also capitalized.
Terms Associated with God

Here is where the capitalization rules really get sticky. CMOS does lay out its standards, but authors and publishing houses alike tend to take a moral stance on whether or not to capitalize certain words, and they are not always willing to yield their positions.
As a good rule of thumb:
- If you are self-publishing, you may set your own rules; just make sure you follow them consistently!
- If you are going through a traditional publisher and you do not agree with their rules, explain your position and see if they will make allowances.
- If the publisher will not budge, the publisher wins!
As far as CMOS is concerned, all proper names are obviously capitalized. Other associated terms are capitalized or lowercase as follows:
- Alternative Names are capitalized: e.g. the Trinity, the Lord, Holy Spirit
- Platonic Ideas Attributed to God are capitalized: e.g. Truth, Good, Goodness, Holy, Holiness
- Pronouns Referring to God are lowercase: e.g. he, his, him
- Church as an Institution is lowercase: e.g. the early church
- Titles of Religious Texts are capitalized: e.g. the Bible, the Torah, the Dead Sea Scrolls
- Named Prayers are capitalized: e.g. the Lord’s Prayer
- Major Events and Concepts are capitalized: e.g. Creation, the Crucifixion, the Diaspora, the Fall
- Celestial Places are lowercase: e.g. heaven, hell, purgatory, outer darkness
NOTE: Platonic ideas embody a perfect state attributable only to God. So, these terms would be capitalized to distinguish between God’s perfect state and the lowercase use of these words that describes man’s imperfect, partial representation of God’s perfect state. Truth is absolute truth, Good is absolute goodness, etc.
This concludes our general overview of the rules for capitalization. Again, you will need to review your style guide for the complete set of rules. If you are setting your own rules, it is advisable to maintain your own style sheet to refer back to as you are writing your manuscript.
Stay tuned for our next mechanics post, which will cover a number of commonly misused words.
Leave a Reply