1. a small toy duck, typically made of rubber or plastic, often used as a bath toy for children
Usage: informal; often used in child-directed speech
2. a term of endearment or affectionate form of address
Usage: informal; chiefly British

Examples

• The toddler squeezed the yellow duckie during bath time.
• My daughter loves playing with her rubber duckies in the tub.
• Come here, duckie, and give me a hug.
• The bath toy collection included several duckies of different sizes.
• She called everyone 'duckie' as a friendly greeting.