The number of regular recurrences in a given time, e.g., heartbeats, sound vibrations. [L. frequens, repeated, often, constant]
- best f. SYN: characteristic f..
- critical flicker fusion f. the minimal number of flashes of light per second at which an intermittent light stimulus no longer stimulates a continuous visual sensation.
- f. domain the expression of a function by its amplitude and phase at each component f., usually as determined by Fourier analysis.
- dominant f. the f. occurring most often in an electroencephalogram.
- f. encoding in magnetic resonance imaging, a method of varying the magnetic field strength by location to encode the location of each voxel uniquely in one direction.
- fundamental f. 1. the principal component of a sound wave, which has the greatest wavelength; 2. tone produced by the vibration of the vocal folds before the air reaches any cavities.
- gene f. 1. the probability that a gene picked at random from a defined population is of a particular type; 2. epidemiologically, the proportion of genes in a population that are of the particular type; 3. statistically, the estimate of either of the foregoing two quantities.
- Larmor f. in magnetic resonance, the precessional f., n0, of magnetic nuclei in a plane perpendicular to the direction of the external magnetic field; v0 = γB0/2π, where B0 is the magnetic field strength and γ is the magnetogyric ratio.
- f. of micturition micturition at short intervals; it may result from increased urine formation, decreased bladder capacity, or lower urinary tract irritation.
- mutational f. the proportions of mutations in a population.
- nearest neighbor f. the f. by which certain types of entities or structures are immediately adjacent to a given structure.
- resonant f. the f. at which individual magnetic nuclei absorb or emit radiofrequency energy in magnetic resonance studies. SYN: resonance (6).
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1) the number of individuals in a single class when objects are classified according to variations in a set of one or more specified attributes
2) the number of repetitions of a periodic process in a unit of time
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n.
(of urine) the passage of urine more than seven times a day: a lower urinary tract symptoms that usually indicates genitourinary disorders and diseases but also accompanies polyuria.
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fre·quen·cy (freґkwən-se) 1. the number of occurrences of a periodic or recurrent process per unit time. 2. the number of occurrences of a particular event or the number of members of a population or statistical sample falling in a particular class. Symbol f. 3. relative f.Medical dictionary. 2011.