n. 1. The act or process of adding; addition. 2. A sum or aggregate. 3. A concluding argument after the presentation of a legal case, especially an argument made to a judge or jury by an attorney for a party as to why that party should prevail. 4. Physiology The process by which multiple or repeated stimuli can produce a response in a nerve, muscle, or other part that one stimulus alone cannot produce. [New Latin summātiō, summātiōn-, from Late Latin summātus, past participle of summāre, to sum up, from Latin summa, sum; see SUM.] |
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