periodic
英 [,p??r?'?d?k]
美 [,p?r?'ɑd?k]
中文詞源
periodic 周期性的來自period,周期，時(shí)期。
英文詞源
- periodic (adj.)
- 1640s, from French périodique (14c.), from Latin periodicus, from periodus (see period).
Periodic table in chemistry (1889) is from notion of the arrangement, in which similar properties recur at intervals in elements in the same area as you read down the rows of the table. This sense of the word is attested from 1872 (periodic law).
雙語例句
- 1. There may be periodic police "sweeps" of crime in the area.
- 警方可能對該地區(qū)的犯罪活動(dòng)進(jìn)行定時(shí)的“掃蕩”。
來自柯林斯例句
- 2. Periodic checks are carried out on the equipment.
- 設(shè)備定期進(jìn)行檢查。
來自《權(quán)威詞典》
- 3. Long long ago, we knew the periodic motion of a planet.
- 很久以前, 我們就知道行星的周期運(yùn)動(dòng).
來自《簡明英漢詞典》
- 4. These arrangements are subject to periodic reviews.
- 這幾項(xiàng)安排每隔一定時(shí)間須予復(fù)查.
來自《現(xiàn)代漢英綜合大詞典》
- 5. Periodic checks are taken to ensure that high standards are maintained.
- 定期檢查以確保維持高水準(zhǔn)。
來自辭典例句