The Collaborative International Dictionary of English v.0.48:
Decimeter \Dec"i*me`ter\, Decimetre \Dec"i*me`tre\, n. [F. d['e]cim[`e]tre; pref. d['e]ci- tenth (fr. L. decimus) + m[`e]tre. See Meter.] A measure of length in the metric system; one tenth of a meter, equal to 3.937 inches. [1913 Webster]WordNet (r) 3.0 (2006):
decimetre n 1: a metric unit of length equal to one tenth of a meter [syn: decimeter, decimetre, dm]