A characteristic is a quality or feature that helps identify or describe someone or something. When you list the characteristics of your best friend, you might mention that they're funny, loyal, and love basketball. When scientists describe the characteristics of mammals, they note features like warm blood, fur, and the ability to nurse their young.

Characteristics are like identifying marks that help you recognize and understand things. Your teacher might say that careful handwriting is characteristic of your work, meaning it's typical of you, something people expect to see from you.

Some characteristics are physical: a giraffe's long neck, a lemon's sour taste, or the rough texture of tree bark. Others describe personality or behavior: a characteristic smile, a characteristic way of solving problems, or the characteristic honesty of someone who always tells the truth.

When something is described as characteristic of a person or thing, it means the quality is so typical that it helps define them. If your sister always arrives exactly on time, you might say that punctuality is characteristic of her. The word helps us notice patterns and understand what makes each person, animal, or thing unique.