head sea

9.9

Waves that move directly against a ship as it sails

noun

Specialized

: mar de proa

Navigating in head seas can be very uncomfortable due to the waves hitting the bow directly.
soft in a head sea
big head seas

Examples

Sailing into a head sea can make for a rough and uncomfortable journey for everyone aboard.
Engineers must account for the impact of a head sea when designing the bow of an ocean-going vessel.
The ship slowed considerably as it encountered a strong head sea on its way to the harbor.
The head sea is fierce today.
Can you see the head sea ahead?
The boat struggled to maintain stability as it plowed through the challenging head sea.
When sailing into head seas, it is important to reduce speed to prevent damage to the vessel.

Surface Forms

head sea singular

head seas plural

Morphology

head + sea

The compound is directly built from 'head' (front/fore) + 'sea' (the ocean/waves), so a learner who knows both words can infer it refers to the sea/waves encountered at the front of a vessel — i.e., waves running against the ship's movement. This parallels transparent patterns like 'headwind' and is therefore readily interpretable by a B1 learner despite being a nautical term.

Etymology

Head sea comes from sailors who saw waves hitting the head, the front of the ship. Because these waves come against the ship's direction and make the trip slow and rough, head sea means 'waves coming straight at a ship'.