1. reefing - Noun
2. reefing - Verb
of Reef
The process of taking in a reef.
Source: Webster's dictionaryOn a small boat with only jib and mainsail this is done by furling the jib and by partially lowering the mainsail, a process called 'reefing the main'. Source: Internet
Reducing or reefing the total sail area will have the same effect and many boats will sail faster with less sail in a stiff breeze due to the reduction in underwater drag. Source: Internet