D
/di:/
Học thuậtThân thiện
Definition
Noun:
- The fourth letter of the modern English alphabet: "d" is a consonant and the fourth letter in the English alphabet.
- The Roman numeral for 500: In the Roman numeral system, "D" represents the number five hundred.
- A musical note: In the system of solfège, "D" is the note "re" and is the second note of the C major scale.
- A shape or object resembling the letter D: Something that has the curved and straight form of the capital letter D.
Adjective:
- Denoting a quantity of 500: Used before a noun to specify an amount of five hundred units. (This usage is derived from its role as a Roman numeral).
Usage Examples
Noun:
- The word "dog" starts with the letter d.
- In Roman numerals, D equals 500.
- The first string on the violin is tuned to D.
- The carpenter used a D-ring to secure the strap.
Adjective:
- The manuscript is from around D CCC (500 + 300 = 800) AD. (Note: This adjectival use is specific to numeral notation).
Advanced Usage
"D" as a grade: In academic grading systems in some countries, "D" often represents a below-average but passing grade.
- He was disappointed to get a D in chemistry, but at least he passed.
"D" as a size or type: Used in product classifications, such as battery sizes (e.g., D-cell) or bra cup sizes.
- This flashlight requires two D batteries.
"D" in physics: Can stand for specific quantities, such as "diffusion coefficient" or "electric displacement field," but these are specialized scientific symbols, not general uses of the word "d".
Variants and Related Words
- D. (abbreviation): An abbreviation for titles like "Doctor" or "Drive" (as in a road).
- The appointment is with D. Smith.
- d. (abbreviation): An abbreviation for "died," "penny" or "pence" (in old British currency), or "day."
- The inscription read: John Doe, b. 1920, d. 2005.
Synonyms
- Five hundred: The cardinal number equivalent to the Roman numeral D.
- Re: The solfège name for the musical note D.
Related Phrases
- D-Day: A military term for the designated day an operation begins, now commonly used for any important day.
- The project's D-Day is next Monday.
- D-List: Referring to the lowest category of fame or celebrity.
- After the scandal, the actor was relegated to the D-list.
Related Idioms
- Mind your p's and q's: While not containing "d," this idiom about being careful with details is analogous to being careful with letters. A potential idiom involving "d" is less common, but one could say "from A to D" to imply a partial range or incomplete coverage, contrasting with the full "from A to Z."
- His report only covered the topic from A to D, missing many key points.
Adjective
- denoting a quantity consisting of 500 items or units
Noun
- the 4th letter of the Roman alphabet
- the cardinal number that is the product of one hundred and five
- a fat-soluble vitamin that prevents rickets