megaton

power

bomb / (fishery jargon) bivalve shell that contains mud instead of flesh

to hold, to carry something / to have, to possess / to hold up, to maintain

holding, possession / wear, durability

continuative of 持つ

grade, rank, class, level

rank / (school) a class / (typography) a unit equal to 1 H (ha) and 0.25 mm, abbreviated as Q, which happens to be the initial of English quarter; Q is used for font size, while ha is used for spacing

dirty bomb

a time bomb (bomb with a timeout mechanism)