What is "cross sea"

Cross \Cross\ (kr[o^]s), a.

1. Not parallel; lying or falling athwart; transverse; oblique; intersecting.

   The cross refraction of the second prism.
   --Sir I. Newton.

2. Not accordant with what is wished or expected; interrupting; adverse; contrary; thwarting; perverse. ``A cross fortune.''
   --Jer. Taylor.

   The cross and unlucky issue of my design.
   --Glanvill.

   The article of the resurrection seems to lie marvelously cross to the common experience of mankind.
   --South.

   We are both love's captives, but with fates so cross, One must be happy by the other's loss.
   --Dryden.

3. Characterized by, or in a state of, peevishness, fretfulness, or ill humor; as, a cross man or woman.

   He had received a cross answer from his mistress.
   --Jer. Taylor.

4. Made in an opposite direction, or an inverse relation; mutually inverse; interchanged; as, cross interrogatories; cross marriages, as when a brother and sister marry persons standing in the same relation to each other. Cross action (Law), an action brought by a party who is sued against the person who has sued him, upon the same subject matter, as upon the same contract. --Burrill. Cross aisle (Arch.), a transept; the lateral divisions of a cruciform church. Cross axle.

   1. (Mach.) A shaft, windlass, or roller, worked by levers at opposite ends, as in the copperplate printing press.

   2. A driving axle, with cranks set at an angle of 90[deg] with each other.

      Cross bedding (Geol.), oblique lamination of horizontal beds.

      Cross bill. See in the Vocabulary.

      Cross bitt. Same as Crosspiece.

      Cross bond, a form of bricklaying, in which the joints of one stretcher course come midway between those of the stretcher courses above and below, a course of headers and stretchers intervening. See Bond, n., 8.

      Cross breed. See in the Vocabulary.

      Cross breeding. See under Breeding.

      Cross buttock, a particular throw in wrestling; hence, an unexpected defeat or repulse.
      --Smollet.

      Cross country, across the country; not by the road. ``The cross-country ride.''
      --Cowper.

      Cross fertilization, the fertilization of the female products of one physiological individual by the male products of another, -- as the fertilization of the ovules of one plant by pollen from another. See Fertilization.

      Cross file, a double convex file, used in dressing out the arms or crosses of fine wheels.

      Cross fire (Mil.), lines of fire, from two or more points or places, crossing each other.

      Cross forked. (Her.) See under Forked.

      Cross frog. See under Frog.

      Cross furrow, a furrow or trench cut across other furrows to receive the water running in them and conduct it to the side of the field.

      Cross handle, a handle attached transversely to the axis of a tool, as in the augur.
      --Knight.

      Cross lode (Mining), a vein intersecting the true or principal lode.

      Cross purpose. See Cross-purpose, in the Vocabulary.

      Cross reference, a reference made from one part of a book or register to another part, where the same or an allied subject is treated of.

      Cross sea (Naut.), a chopping sea, in which the waves run in contrary directions.

      Cross stroke, a line or stroke across something, as across the letter t.

      Cross wind, a side wind; an unfavorable wind.

      Cross wires, fine wires made to traverse the field of view in a telescope, and moved by a screw with a graduated head, used for delicate astronomical observations; spider lines. Fixed cross wires are also used in microscopes, etc.

      Syn: Fretful; peevish. See Fretful.

n. (context nautical English) a sea whose current runs contrary to that of the wind

In surface navigation, a cross sea is a sea state with two wave systems traveling at oblique angles. This may occur when water waves from one weather system continue despite a shift in wind. Waves generated by the new wind run at an angle to the old, creating a shifting, dangerous pattern. Two weather systems that are far from each other may create a cross sea when the waves from the systems meet, usually at a place far from either weather system. Until the older waves have dissipated, they create a sea hazard among the most perilous. This sea state is fairly common and a larger percentage of ship accidents were found to have occurred in this state.

A cross swell is generated when the wave systems are longer period swell, rather than short period wind generated waves.