C
Abbreviation with 11 meanings
| Stands for | Cup |
|---|---|
| Meanings | 11 |
| Categories | Units & Measurements, Science & Engineering, Writing & Everyday, Sports, Medical |
| Also written | c, c., c̄ |
C has 11 meanings. The most common are Cup (cooking) and Degree Celsius (engineering unit); it can also stand for Carbon, Circa (around, approximately), Centi- (hundredth), Coulomb and Speed of light, plus 4 more listed below.
Meanings of C at a glance
| # | C stands for | Context |
|---|---|---|
| 1 | Cup | Units & Measurements › Cooking |
| 2 | Degree Celsius | Units & Measurements › Engineering Unit |
| 3 | Carbon | Science & Engineering › Chemical Element |
| 4 | Circa (around, approximately) | Writing & Everyday › Latin |
| 5 | Centi- (hundredth) | Units & Measurements › Metric and SI Unit |
| 6 | Coulomb | Units & Measurements › Metric and SI Unit |
| 7 | Speed of light | Science & Engineering › Physics |
| 8 | Catcher | Sports › Baseball |
| 9 | Center (American football) | Sports › American Football |
| 10 | Cum (with) | Medical › Prescription |
| 11 | Complex numbers | Units & Measurements › Math |
1. Cup (c)
Units & Measurements · Cooking Abbreviations
The main volume measure in American recipes for flour, sugar, liquids and chopped ingredients. A US customary cup is 8 US fluid ounces, about 236.6 mL, or 16 tablespoons; US nutrition labels use a rounded legal cup of exactly 240 mL.
Example: Combine 2 c all-purpose flour, 3/4 c sugar and 1 c buttermilk in a large bowl.
Also written C, c. or cup; a capital C can be confused with the Celsius symbol in oven directions, so context matters. Cup sizes differ by country: the metric cup used in Australia, New Zealand and Canada is 250 mL, the old British imperial cup was about 284 mL (half an imperial pint), and the Japanese cup is 200 mL. Dry ingredients vary in weight depending on how they are scooped, so many bakers prefer grams.
2. Degree Celsius
Units & Measurements · Engineering Unit Abbreviations
The temperature scale for weather, cooking and medicine in nearly every country except the US. Water freezes at 0°C and boils at 100°C at sea level, and normal body temperature is about 37°C.
Example: Tomorrow's high will be 24 C with a light breeze.
Swedish astronomer Anders Celsius proposed the scale in 1742 with the numbers reversed, 0 for boiling and 100 for freezing; it was flipped after his death. "Centigrade" was officially replaced by "Celsius" in 1948. A change of 1°C equals 1 kelvin or 1.8°F. In recipes, a lone C can also mean cup.
3. Carbon
Science & Engineering · Chemical Element Abbreviations
Element 6 forms the backbone of every organic molecule, from sugars and proteins to plastics and fuels. Its atoms bond into strikingly different solids: diamond, the hardest natural material, graphite, soft enough for pencil cores, plus graphene and fullerenes. Radiocarbon dating relies on carbon-14, with a half-life of about 5,730 years.
Example: Combustion analysis gave C 40.0% and H 6.7%, consistent with the formula of glucose.
Known since prehistory as charcoal and soot, carbon takes its name and symbol from Latin carbo (coal, charcoal); Lavoisier listed it as an element in 1789. Since 1961 the isotope carbon-12 has anchored the scale of atomic masses, with one atom defined as exactly 12 daltons. In climate discussions "carbon" is often shorthand for carbon dioxide, which is CO2, not C.
4. Circa (around, approximately) (c.)
Writing & Everyday · Latin Abbreviations
Placed before a date or number that is approximate, most often a historical year that cannot be pinned down exactly. It appears in museum labels, biographies, timelines, auction catalogs and bibliographies.
Example: The manuscript, copied c. 1150 in a Benedictine scriptorium, is the oldest surviving copy of the poem.
Many American publishers, following Chicago, prefer the form ca., while British publishers and Wikipedia favor c.; both are read as "circa," never as letters, and an older variant is circ. Use it only with numbers and dates, not with descriptive phrases, and never together with "about." It is set in roman type before the number with a space, and ranges such as c. 1150-60 are acceptable.
5. Centi- (hundredth) (c)
Units & Measurements · Metric and SI Unit Abbreviations
One hundredth (10^-2) of a unit. Nearly all its everyday use is in the centimeter, plus the centiliter on European drinks menus and the centistoke and centipoise of fluid viscosity.
Example: The wine list pours 15 cL by the glass and 75 cL by the bottle.
From Latin centum, hundred; part of the 1795 metric system. Centi- is one of four prefixes (with hecto-, deca- and deci-) that do not follow the thousand-step pattern used everywhere else in SI. In recipes a lowercase c usually means cup, so the context of the line decides.
6. Coulomb
Units & Measurements · Metric and SI Unit Abbreviations
Electric charge carried by a current of one ampere in one second, the SI unit of charge. One coulomb is the charge of about 6.24 × 10^18 electrons, and a lightning stroke typically transfers somewhere from a few to tens of coulombs.
Example: The capacitor stores 0.02 C of charge at its rated voltage.
Named after French physicist Charles-Augustin de Coulomb, who formulated the inverse-square law of electrostatic force in the 1780s. Since 2019 the elementary charge has been fixed at exactly 1.602176634 × 10^-19 C. Battery capacity in mAh is also a charge measure: 1 mAh equals 3.6 C. A capital C elsewhere often means degrees Celsius or, in recipes, cup.
7. Speed of light (c)
Science & Engineering · Physics Abbreviations
Speed of light in a vacuum, exactly 299,792,458 meters per second, about 300,000 kilometers per second or 186,000 miles per second. It is the universal speed limit for matter and information and appears in Einstein's E = mc2.
Example: Light from the Sun, traveling at c, takes about 8 minutes 20 seconds to reach Earth.
Since 1983 the meter has been defined from c, which made its value exact by definition. Ole Rømer made the first quantitative estimate in 1676 from timings of Jupiter's moons. The symbol is thought to come from Latin celeritas (swiftness). Light travels more slowly in glass and water.
8. Catcher
Sports · Baseball Abbreviations
Defensive player who squats behind home plate, position number 2, receiving pitches, calling the game with the pitcher and throwing out base stealers. Catching is the most physically demanding position.
Example: He started at C for the first time since his knee surgery.
Catchers wear protective gear ("the tools of ignorance"), and pitch framing, the skill of making borderline pitches look like strikes, became a measured skill in the 2010s. Johnny Bench and Yogi Berra are among the greatest catchers.
9. Center (American football)
Sports · American Football Abbreviations
Offensive lineman in the middle of the line who snaps the ball between his legs to the quarterback to start each play and then blocks. Centers usually make the protection calls that set blocking assignments for the whole line.
Example: The rookie C made the line calls after the veteran went down with an ankle injury.
The center is the one lineman who handles the ball on every play. In shotgun formation he snaps it several yards back rather than directly into the quarterback's hands. Basketball and hockey also abbreviate center as C, for entirely different roles.
10. Cum (with) (c̄)
Medical · Prescription Abbreviations
Medical shorthand meaning "with", written as a lowercase c with a bar over it in charts, prescriptions and handwritten notes, as in "take c̄ food". Its opposite, s̄ (sine), means "without".
Example: Take one tab c̄ meals; pt reports nausea s̄ vomiting.
Latin "cum", "with". Because the overbar is easily lost in typing or faxing, "c̄" can become a plain "c" or be misread, so many institutions require "with" to be written out. The same Latin word appears in "cum laude" and "summa cum laude".
11. Complex numbers
Units & Measurements · Math Abbreviations
The set of complex numbers a + bi, where i² = −1, written in blackboard bold as ℂ. Every polynomial equation with complex coefficients has a solution in C, the fundamental theorem of algebra.
Example: The equation x² + 1 = 0 has no real roots but two roots in C: i and −i.
Complex numbers are pictured on the complex plane, with real and imaginary axes. Electrical engineers use them to analyze AC circuits and signals, writing j instead of i to avoid confusion with current. Carl Friedrich Gauss gave an influential early proof of the fundamental theorem of algebra in 1799.
Related abbreviations
More cooking abbreviations
- AP – All-purpose (flour)
- BBE – Best before end
- BBQ – Barbecue
- BLT – Bacon, lettuce and tomato (sandwich)
- DF – Dairy-free
- DOC – Denominazione di Origine Controllata (controlled designation of…
- doz – Dozen
- dsp – Dessert spoon
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More engineering unit abbreviations
- AWG – American wire gauge
- bar – Bar
- bhp – Brake horsepower
- BTU – British thermal unit
- Cal – Food Calorie (kilocalorie)
- cfm – Cubic feet per minute
- Ci – Curie
- CID – Cubic inch displacement
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This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.