reef

noun

/riːf/

a long line of rocks or sand near the surface of the sea礁；礁脉
- a coral reef珊瑚礁
- the Great Barrier Reef大堡礁
see also barrier reefTopics Geographyb2
a part of a sail that can be tied or rolled up to make the sail smaller in a strong wind缩帆部；帆的可收缩部

词源noun sense 1 late 16th cent. (earlier as riff): from Middle Low German and Middle Dutch rif, ref, from Old Norse rif, literally ‘rib’, used in the same sense. noun sense 2 Middle English: from Middle Dutch reef, rif, from Old Norse rif, literally ‘rib’, used in the same sense.

reef

verb

/riːf/

(specialist)

动词形式

present simple I / you / we / they reef	/riːf/ /riːf/
he / she / it reefs	/riːfs/ /riːfs/
past simple reefed	/riːft/ /riːft/
past participle reefed	/riːft/ /riːft/
-ing form reefing	/ˈriːfɪŋ/ /ˈriːfɪŋ/

reef something to make a sail smaller by tying or rolling up part of it收帆；卷起缩帆部；叠起缩帆部
- They set sail with the sails reefed against the strong winds.他们扬帆起航，逆风行驶。
Collocations Dictionary
Reef is used with these nouns as the object:
sail
词源verb Middle English: from Middle Dutch reef, rif, from Old Norse rif, literally ‘rib’, used in the same sense.