composed
The definition for composed is "Calm." Used in a sentence: Although her stomach was in knots, the actress appeared perfectly composed when she took the stage.
corroborate
The definition for corroborate is "To support with evidence." Used in a sentence: "Unless you can corroborate your story, it will not be admissible in court," the attorney told his client.
extenuating
The definition for extenuating is "Partially excusing." Used in a sentence: The extenuating circumstance of Calvin's illness caused the teacher to excuse his lateness.
gargantuan
The definition for gargantuan is "Gigantic." Used in a sentence: The gargantuan monster towered over the ten–story bulding.
precept
The definition for precept is "A general rule of action." Used in a sentence: All the students know Mrs. Brown's strict precept; no talking in class.