direction of motiondirection of polarizationdirection of polirizationdirection of propagationdirection of rotationdirectionaldirectional antennadirectional characteristicdirectional coplerdirectional deamdirectional douplerdirectional hydrohonepdirectional microphonedirectional patternsdirectional phase shifterdirectivedirectivitydirectivity factordirectivity index directional gaindirectivity pattern beam pattern directional response patterndirectivity signaldirectiy lonizing particiesdirectlydirectly coupled amplifierdirectordirectorydirectory serverdirichletdischargedischarge capacitydischarge circuitdischarge currentdischarge curvedischarge diagramdischarge energydischarge gapdischarge pathdischarge potentialdischarge voltagedischargingdiscolordiscolorationdiscone antennadisconnectdiscontinuitydiscontinuousdiscovery framediscretediscrete circuitdiscrete compnent microcircuit
