1. sweetie, doll [noun] [de mop, de moppen]

The informal diminutive of "mop" is "moppie". Both can be used. Mind that it is a bit old-fashioned and associated with lower class social environments. Also, it can only be used to address females.

Examples:
– "<bouwvakker:> Hé moppie! Wat zie jij er goed uit!!"
("<construction worker:> "Hey sweetie! You’re lookin’ good!!)

– "<in een Amsterdams bruin café:> Luister eens moppie, het is dat je vent staat te kijken, want anders had ik het wel geweten!"
("<in a brown pub/bar in Amsterdam:> Listen sweetie, if it weren’t for your man looking at us, I would have taken my chance!" Literally: "…, it is that your man is looking, because otherwise I would have known!" Here, the use of the verb "staan" is to indicate that the man is in the activity of looking.)

– "Ik weet het mop, ik had het beloofd, maar ik moet vanavond weer overwerken!"
("I know sweetie, I promised, but tonight I have to work overtime again!")

2. joke, jest [noun] [de mop, de moppen]

Examples:
– "Weet jij een leuke mop?"
("Do you know a good joke?")

– "Mijn oom is erg goed in het vertellen van moppen."
("My uncle is really good at telling jokes.")

Related words:
– "Moppentappen": to tell jokes. Literally "to draft jokes".
– "Grap": joke.
– "Grappenmaker": one who makes jokes.

3. mop [noun] [de mop, de mops]

Example:
– "Heb jij de mop gezien? Ik wil de keukenvloer dweilen."
("Have you seen the mop? I want to mop the kitchen floor.")

Related words:
– "Zwabber": mop. This word is actually more common than "mop".
– "Dweil": floor-cloth, rag, mop (if on a stick).