discern
The definition for discern is "To recognize as separate as distinct." Used in a sentence: The pastry connoisseur was able to discern Swiss from Belgian chocolate.
gruff
The definition for gruff is "Rough or stern in manner or speech." Used in a sentence: Heidi's grandfather was gruff, barking stern orders and hardly smiling.
oblivious
The definition for oblivious is "Lacking awareness." Used in a sentence: Love–struck Charlie was oblivious to everyone but the object of his affection.
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.
scamper
The definition for scamper is "To run quickly." Used in a sentence: The frightened kitten scampered away from the butterfly.