詰つめ開ひらきで

expression

at close reach; at close haul

Sailing term: sailing as close to the wind as possible while still making headway. The phrase is a set expression used adverbially.

See also: 詰め開き

• ヨットは詰つめ開ひらきで風かざ上かみに向むかって進すすんだ。

  The yacht sailed close-hauled toward the windward side.