orthogonal— On a wave-refraction diagram, a line drawn perpendicularly to the wave crests. 



oscillation— A periodic motion backward and forward. To vibrate or vary above and below a 

 mean value. 



pierhead line— The limiting line to which any pier or dock structure can extend into the 

 main channel area. 



pitch— The rotational oscillations of a craft about its transverse axis under wave excitation. 



prevailing winds— The characteristic and most commonly occurring winds, both in 

 magnitude and direction, observed at a given location. 



profile height— The quotient obtained by dividing the cross-sectional area of a craft's end 

 (or side) profile above the water surface by the overall width (or length) of that craft. 



project bottom depth— The design depth of a basin or channel, usually measured below a 

 given water surface elevation such as mean low water. Authorized depth to be 

 maintained. 



protected water— Sheltered water areas, protected either by natural or manmade wave 

 barriers, which are adequate for the safe mooring of watercraft. 



pumpout station— A facility for removal of sanitary wastes from a boat's holding tank or 

 head. 



reach— A length, distance, or leg of a channel or other watercourse. 



rebar— Reinforcing bar or rod imbedded in a concrete structure. 



refraction diagram— A drawing showing successive positions of a wave crest and/or 

 orthogonals in a given area for a specific deepwater wave period and direction. 



residual wave action— Wave action that remains after an incident wave has been partially 

 attenuated, reflected, absorbed, or otherwise modified by any natural or manmade 

 obstacle. 



resonance— The phenomenon of amplification of a free wave or oscillation of a system by a 

 forced wave or oscillation of exactly equal period. The forced wave may arise from an 

 impressed force upon the system or from boundary conditions. 



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