megavitamin

As a noun terms

is .

As an adjective megavitamin is

involving megadoses of vitamins.

As a noun vitamin

is vitamin.

As an adjective megavitamin is

involving megadoses of vitamins.

As a noun megadose

is a dose of drug or vitamin far exceeding the normal or recommended amount, and usually given intentionally compare overdose.

As a verb megadose

is to dose (a patient) with a very large amount of a drug.

As an adjective megavitamin is

involving megadoses of vitamins.