M66 may refer to:
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M66 (New York City bus), a New York City Bus route in Manhattan
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M-66 (Michigan highway), a state highway in Michigan
*
M66 motorway
The M66, also known as the Bury Easterly Bypass, is a motorway in Lancashire and Greater Manchester, England. It is long and provides part of the route between the M62 and M60 motorways and the M65, with the rest being provided by the A56. ...
, a motorway in Greater Manchester, England
*
Black Magic M66
is a cyberpunk manga written and illustrated by Masamune Shirow. It was first published as a ''dōjinshi'' in 1983, and was later reprinted in ''tankōbon'' format by Seishinsha in 1985. The series was later adapted into an OVA in 1987 whic ...
, the classification of a fictional android
*
Messier 66, a spiral galaxy in the constellation Leo
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Soltam M-66
The M-66 is a 160 mm mortar manufactured by Soltam of Israel. The weapon was based on an earlier 160 mm design, the M-58 mortar by Vammas of Finland. It can fire a 38 kg (84 lb) HE bomb out to a maximum range of 9,600 m and r ...
, a 160 mm mortar manufactured in Israel
* Smith & Wesson Model 66 (S&W M66), a variant of
Smith & Wesson Model 19 (S&W M19) revolver
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