Modifiers matching duck:

• tenacious,
• jealous,
• paranoid,
• rare,
• daffy,
• determined,
• boastful,
• slobbery,
• bullying,
• insecure,
• optimistic,
• pushy,
• indigenous,
• larger,
• large,
• smaller,
• brash,
• unusual,
• native,
• breeding,
• wild,
• marine,
• short-tempered,
• lisping,
• aggressive,
• zany,
• here,
• common,
• small,
• domestic,

Simple categories matching lisping:

• person,
• child,
• villain,
• duck,