I made this one up. Actually, I discovered it by accident because of a fortuitous typo. It means an excessive amount of mothering, a lotta mom, a lotta maternal attention. There’s no value judgment in the word; it can be both positive and negative.
Positive – All that mombardment when I was sick on Monday really helped me get back on my feet by Tuesday.
Negative – “Did you finish your homework, your piano practicing, your chores?” So much mombardment is stifling.