augment
The definition for augment is "To make greater." Used in a sentence: Wanda read the dictionary every night to augment her vocabulary.
avian
The definition for avian is "Relating to birds." Used in a sentence: The old man affectionately referred to pigeons as his "avian friends."
retroactive
The definition for retroactive is "effective as of a prior time or condition." Used in a sentence: The retroactive law made even past infractions punishable.
servile
The definition for servile is "Fearfully submissive." Used in a sentence: Felicia's servile attitude annoyed her boss, who preferred an assistant with more backbone.
sociable
The definition for sociable is "Inclined to seek companionship." Used in a sentence: The sociable Glenda was delighted to receive the party invitation.