n. pl. quan·ta (-tə) 1. Physics a. The smallest amount of a physical quantity that can exist independently, especially a discrete quantity of electromagnetic radiation. b. This amount of energy regarded as a unit. 2. A quantity or amount. 3. A specified portion. 4. Something that can be counted or measured. 5. A unit of acetylcholine, released at the synaptic cleft of a neuromuscular junction. adj. Relating to or based upon quantum theory. [Latin, from neuter of quantus, how great; see QUANTITY.] |
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