Definition of "intracellular" []

• Occurring or situated within a cell or cells: intracellular fluid. (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Action potentials almost always generate large increases in intracellular calcium to exert any biological effect such as the release of neurotransmitters to excite or inhibit the next neuron in the pathway."
• "Fluid inside your cells is called intracellular fluid and the fluid outside your cells is called extracellular fluid."
• "Fully conscious of the insuperable difficulties of explaining at present the innermost mechanism by which this inertness was overcome, Warburg decided to investigate the nature of the mysterious substance that acts as the primus motor in intracellular combustion."