Total lung capacity: the volume in the lungs at maximal inflation, the sum of VC and RV.
TV
Tidal volume: that volume of air moved into or out of the lungs in 1 breath (TV indicates a subdivision of the lung; when tidal volume is precisely measured, as in gas exchange calculation, the symbol TV or VT is used.)
RV
Residual volume: the volume of air remaining in the lungs after a maximal exhalation
ERV
Expiratory reserve volume: the maximal volume of air that can be exhaled from the end-expiratory position
IRV
Inspiratory reserve volume: the maximal volume that can be inhaled from the end-inspiratory level
IC
Inspiratory capacity: the sum of IRV and TV
IVC
Inspiratory vital capacity: the maximum volume of air inhaled from the point of maximum expiration
VC
Vital capacity: the volume of air breathed out after the deepest inhalation.
VT
Tidal volume: that volume of air moved into or out of the lungs during quiet breathing (VT indicates a subdivision of the lung; when tidal volume is precisely measured, as in gas exchange calculation, the symbol TV or VT is used.)
FRC
Functional residual capacity: the volume in the lungs at the end-expiratory position
RV/TLC%
Residual volume expressed as percent of TLC
VA
Alveolar gas volume
VL
Actual volume of the lung including the volume of the conducting airway.
FVC
Forced vital capacity: the determination of the vital capacity from a maximally forced expiratory effort
FEVt
Forced expiratory volume (time): a generic term indicating the volume of air exhaled under forced conditions in the first t seconds
FEV1
Volume that has been exhaled at the end of the first second of forced expiration
FEFx
Forced expiratory flow related to some portion of the FVC curve; modifiers refer to amount of FVC already exhaled
FEFmax
The maximum instantaneous flow achieved during a FVC maneuver
FIF
Forced inspiratory flow: (Specific measurement of the forced inspiratory curve is denoted by nomenclature analogous to that for the forced expiratory curve. For example, maximum inspiratory flow is denoted FIFmax. Unless otherwise specified, volume qualifiers indicate the volume inspired from RV at the point of measurement.)
PEF
Peak expiratory flow: The highest forced expiratory flow measured with a peak flow meter
MVV
Maximal voluntary ventilation: volume of air expired in a specified period during repetitive maximal effort
