megaton has definitions from the field of physics
1
[ noun ] (physics) a measure of explosive power (of an atomic weapon) equal to that of one million tons of TNT

Used in print

("Editorials"...)

The biggest nuclear device the United_States has exploded measured some 15 megatons , although our B-52s are said to be carrying two 20 - megaton_bombs apiece .

Related terms

explosive_unit

2
[ noun ] one million tons

Related terms

avoirdupois_unit kiloton

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