function

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The action for which a person or thing is particularly fitted or employed.
2. n. Assigned duty or activity.
3. n. A specific occupation or role: in my function as chief editor.
4. n. An official ceremony or a formal social occasion.
5. n. Something closely related to another thing and dependent on it for its existence, value, or significance: Growth is a function of nutrition.
6. n. Mathematics A variable so related to another that for each value assumed by one there is a value determined for the other.
7. n. Mathematics A rule of correspondence between two sets such that there is a unique element in the second set assigned to each element in the first set.
8. n. Biology The physiological activity of an organ or body part.
9. n. Chemistry The characteristic behavior of a chemical compound, resulting from the presence of a specific functional group.
10. n. Computer Science A procedure within an application.
11. v. To have or perform a function; serve: functioned as ambassador.

Century Dictionary and Cyclopedia

1. n. Fulfilment or discharge of a set duty or requirement; exercise of a faculty or office.
2. n. Activity in general; action of any kind; behavior.
3. n. Power of acting; faculty; that power of acting in a specific way which appertains to a thing by virtue of its special constitution; that mode of action or operation which is proper to any organ, faculty, office, structure, etc.
4. n. That which one is bound or which is one's business to do; business; office; duty; employment.
5. n. An official ceremony. Eccles., a religious service with elaborate ritual and music.
6. n. Any important occasion marked by elaborate ceremonial: extended in recent use to cover social entertainments, as operas, balls, and receptions.
7. n. In mathematics, a mathematical quantity whose value depends upon the values of other quantities, called the arguments or independent variables of the function; a mathematical quantity whose changes of value depend on those of other quantities called its variables. Thus, if the diameter of a circle be conceived to vary in length, the length of the circumference will also vary with it, in accordance with a fixed geometrical law, and is therefore a function of the diameter, the latter being regarded as the independent variable. So in the equation y = ax + b, if x be conceived to vary independently, y will be its function, since its value will vary with each successive value of x. The common algebraic notation is y = f , to be read “y is a function of x.” F, ф, and other letters are often used in place of feminine It is not the special value of fx, but this Quantity considered as variable and as depending upon x, which is called the function. It is even called the same function irrespective of the special values of certain parameters upon which it may depend, and which are considered not as variables, but as constants. The earlier analysts used function to mean merely a power, or continued product of a quantity into itself. The present mathematical meaning first appears in the Latin correspondence between Leibnitz and John Bernoulli Mathematical usage is not precisely settled as to the meaning, and this in two respects. First, as some writers use the word, the possible values of the function depend upon the values of the variables; so that, if y is a function of x, there must be some value which y can take for some value of x, which it cannot take for some other value of x. But other writers hold that two quantities which are functions of a third are functions of each other. For example, if x = tan t and y = tan (t √ 2)+ i tan (t √ 3), they hold that y is a function of x, although it can take every value for every value of x; for there is even here a connection between the values of x and y, so that in the course of any continuous change of x the mode of change of y is somewhat restricted. Secondly, according to the usage of Cauchy and his followers, if an imaginary quantity, X + Yi, be so connected with another. x + yi, that X and Y are each of them functions of x and y, say X = F (x, y) and Y = f (x, y), then the former imaginary is a function of the other; but the majority of mathematicians have restricted the name function to what the school of Cauchy would term monogenous and differentiable functions, although such a restriction is impossible where the variable does not vary continuously. The tendency of recent writers is to give the greatest possible breadth to the application of the term.
8. n. Hence, anything which is dependent for its value, significance, etc., upon something else.
9. n. See the adjectives.
10. n. see the adjectives.
11. n. See the adjectives.
12. n. One of several functions related to in the same manner in which ordinary elliptic functions are related to , being merely transformed elliptic functions.
13. n. See the adjectives.
14. n. a function such that the interval of the variable considered may be so divided into parts that the function is continuous, differentiable, etc., in each part.
15. n. In a generalized sense, a function which has its value unchanged by the substitution for its variable of a certain algebraic function thereof. A periodic function of the second kind is one for which this function is linear.
16. n. Two physical quantities whose several mathematical relations to two other physical quantities are the same.
17. n. which may, for instance, be either limited or unlimited.
18. To perform a function; work; act; functionate; especially, in physiology, to have a function; do or be something physiologically.
19. n. See graph.
20. n. A function differing from that just defined by log/r.

Wiktionary

1. n. What something does or is used for.
2. n. A professional or official position.
3. n. An official or social occasion.
4. n. A relation where one thing is dependent on another for its existence, value, or significance.
5. n. mathematics A relation in which each element of the domain is associated with exactly one element of the codomain.
6. n. computing A routine that receives zero or more arguments and may return a result.
7. n. biology The physiological activity of an organ or body part.
8. n. chemistry The characteristic behavior of a chemical compound.
9. n. anthropology The role of a social practice in the continued existence of the group.
10. v. intransitive to have a function
11. v. intransitive to carry on a function; to be in action

GNU Webster's 1913

1. n. The act of executing or performing any duty, office, or calling; performance.
2. n. (Physiol.) The appropriate action of any special organ or part of an animal or vegetable organism
3. n. The natural or assigned action of any power or faculty, as of the soul, or of the intellect; the exertion of an energy of some determinate kind.
4. n. The course of action which peculiarly pertains to any public officer in church or state; the activity appropriate to any business or profession.
5. n. (Math.) A quantity so connected with another quantity, that if any alteration be made in the latter there will be a consequent alteration in the former. Each quantity is said to be a function of the other. Thus, the circumference of a circle is a function of the diameter. If x be a symbol to which different numerical values can be assigned, such expressions as x2, 3x, Log. x, and Sin. x, are all functions of x.
6. n. (Eccl.) A religious ceremony, esp. one particularly impressive and elaborate.
7. n. A public or social ceremony or gathering; a festivity or entertainment, esp. one somewhat formal.
8. v. To execute or perform a function; to transact one's regular or appointed business.

WordNet 3.0

1. n. a relation such that one thing is dependent on another
2. n. what something is used for
3. v. perform duties attached to a particular office or place or function
4. n. (mathematics) a mathematical relation such that each element of a given set (the domain of the function) is associated with an element of another set (the range of the function)
5. n. a vaguely specified social event
6. n. the actions and activities assigned to or required or expected of a person or group
7. n. a formal or official social gathering or ceremony
8. v. perform as expected when applied
9. n. a set sequence of steps, part of larger computer program
10. v. serve a purpose, role, or function