资料来源 : WordNet®

IV
     n 1: the cardinal number that is the sum of three and one [syn: {four},
           {4}, {tetrad}, {quatern}, {quaternion}, {quaternary}, {quaternity},
           {quartet}, {quadruplet}, {foursome}, {Little Joe}]
     2: administration of nutrients through a vein [syn: {intravenous
        feeding}]