decameter I. de·cam·e·ter\də̇ˈkaməd.ə(r), -deˈ-\noun Etymology: Greek dekametron, from deka ten + metron meter, measure — more at ten, measure : a poetic line of 10 feet II. deca·me·ter\ˈdekəˌmēd.ə(r)\noun Etymology: French décamètre, from déca- deca- + mètre meter : a metric unit of length equal to 10 meters — see metric system table