Just one word, "enema" does it for me. That word has always been an instant turn on, any use, any situation. I immediately envision my legs spread wide and the nozzle going in, and then waiting to hear the click of the clamp release, waiting a few seconds, and then feeling the water rushing in.
The one that chills me is, "Wait till your father comes home!"
"Diaper" has always been a turn on. My mother I guess kept me in diapers forever. I remember liking to pee my diapers and poop in them. I still recall my sister saying, "Mother, he's too old to still be in diapers." I'm really not sure how old I was, maybe 5, possibly 6.
The other one I remember well was me calling out "Wipe me." My mother use to always wipe me after I was toilet trained. My older sister had a fit about that. I think that ended around 6 or so.
Another hot word for me is "Suppository." As a little kid I use to love suppositories during toilet training. They were about 1/8" diameter and about 2" long in a little clear jar with a blue screw on top that held about 25 of them. I used to ask my mother for one even when they were not necessary, and she said "No!" Later, I found them in the old high up medicine cabinet. I made good use of them on my own. None ever said any were missing, I still wonder to this day if my mother noticed them missing and said nothing.
Then, she had some gray ones wrapped in foil and shaped like a bullet of sorts. As a teenager I use to be always sneaking a few of those out of the medicine cabinet (sometimes in the refrigerator) and putting them to good use! Lots of fun I had in those days!
"Kotex" was/is another word I find hot. I tried on some of my mother's once, didn't seem much fun. Then once I got into my sister's Tampons and shoved one up my asshole, that was fun.
And, I had lots of fun growing up! I'm amazed none ever discovered my little sexy adventures and hot words, maybe they did and said nothing.