The Collaborative International Dictionary
Cyclometer
Cyclometer \Cy*clom"e*ter\ (s?-kl?m"?-t?r), n. [Cyclo- + -meter.] A contrivance for recording the revolutions of a wheel, as of a bicycle.
Wiktionary
cyclometer
n. 1 A device that counts the revolutions of a bicycle wheel in order to indicate distance travelled. 2 An instrument for measuring circular arcs. 3 A machine used to decrypt Enigma machine ciphers.
Wikipedia
Cyclometer
The '''cyclometer ''' was a cryptologic device designed, "probably in 1934 or 1935," by Marian Rejewski of the Polish Cipher Bureau's German section (BS-4) to facilitate decryption of German Enigma ciphertext.
Usage examples of "cyclometer".
The Miezer-graph also jumped clear of the paper and the indicator needle of cyclometer visibly bent as if it had come up hard against the stop maximum.