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Sailing Glossary

214 terms and definitions from the Compass Revision Network syllabus, covering nautical terminology, navigation, COLREGs, tides, and more.

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7 terms

AIS boundary in restricted visibility
AIS can support identification and awareness, but targets or hazards may be absent and data may be wrong; do not use it alone to determine collision risk.Restricted Visibility
All-chain scope starting guide
About 4:1 of maximum bow-roller-to-seabed depth in the moderate-condition lesson model. Conditions, bottom, equipment guidance and swing may require another plan.Anchorwork
Anchor bend
A traditional attachment to a ring. A real anchor rode may instead require a thimble, splice or manufacturer-specified termination.Ropework
Anchor signals
Rule 30 normally requires one black ball by day and the applicable all-round white anchor light or lights at night, subject to the Rule's provisions and exceptions.Anchorwork
Anchor watch
A level of vigilance matched to weather, traffic, nearby hazards and consequences, using people, checks and alarms as aids rather than guarantees.Anchorwork
APEM
Appraise, Plan, Execute, Monitor — four connected components of a live passage-planning cycle.Passage Planning
Appraise
Gather current information and test the route, vessel, crew, limitations and genuinely usable alternatives.Passage Planning