sum

英文詞源

sum

sum: [13] Latin summus meant ‘highest’ (a meaning preserved in English summit [15], which is ultimately derived from it); it evolved from an earlier *supmus, a superlative form based on the stem of Latin super ‘above’ (source of English super). When the Romans counted up columns of figures they worked from the bottom upwards, and put the total on top – whence the use of the expression rēs summa, literally ‘highest thing’, for ‘total’. This was eventually shortened to summa, which reached English via Old French summe. Other derivatives in English include consummate [15] and summary [15].
=> consummate, summary, summit

sum (n.)

c. 1300, summe, "quantity or amount of money," from Anglo-French and Old French summe, somme "amount, total; collection; essential point; summing up, conclusion" (13c., Modern French somme), from Latin summa "the top, summit; chief place, highest rank; main thing, chief point, essence, gist; an amount (of money)," noun use (via phrases such as summa pars, summa res) of fem. of summus "highest, uppermost," from PIE *sup-mos-, from root *uper "over" (see super-).

The sense development from "highest" to "total number, the whole" probably is via the Roman custom of adding up a stack of figures from the bottom and writing the sum at the top, rather than at the bottom as now (compare the bottom line).

General sense of "numerical quantity" of anything, "a total number" is from late 14c. Meaning "essence of a writing or speech" also is attested from mid-14c. Meaning "aggregate of two or more numbers" is from early 15c.; sense of "arithmetical problem to be solved" is from 1803. Sum-total is attested from late 14c., from Medieval Latin summa totalis.

sum (v.)

early 14c., "to count, count up, calculate, reckon," from Old French sommer "to count, add up," or directly from Medieval Latin summare, from summa (see sum (n.)). Meaning "briefly state the substance of" is first recorded 1620s (since c. 1700 usually with up). Related: Summed; summing.