beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
gargantuan
The definition for gargantuan is "Gigantic." Used in a sentence: The gargantuan monster towered over the ten–story bulding.
incidental
The definition for incidental is "Minor." Used in a sentence: The accountant advised Justine not to report her incidental expenses.
mandate
The definition for mandate is "An official order or commission to do something." Used in a sentence: Martha reluctantly obeyed the mandate to vacate her apartment.
serenity
The definition for serenity is "Calmness." Used in a sentence: The serenity of the glassy sea soothed the sailors after the big storm.