海かい防ぼうかいぼうFreq.FrequencyTop 100,000Meanings1nouncoastal defenseRefers to military or strategic defense of a coastline. Often used in historical or geopolitical contexts.江え戸ど時じ代だい、幕ばく府ふは海かい防ぼうを強きょう化かするために砲ほう台だいを築きずいた。During the Edo period, the shogunate built batteries to strengthen coastal defense.