Any time an adult does something physical to a child that is manipulative or controlling in some way and is not to the child's benefit (such as grabbing them to keep them from running into the street or touching the BBQ), it is abuse, in my opinion....

For me, it was my uncle... when I was little, it was tickling... and that went on until I was 16 or so. He would not stop even when I screamed at him. And my mother would not do anything to stop it either. When I was a little older, 10 or so, it was too many hugs, particularly from behind, or he would try to kiss me on the lips. When I was older, say 14 or more, he would come up behind me and start rubbing my back or my shoulders. And he would not stop when I told him to. He even went so far as to clenching my shoulders hard enough to bruise the muscles, ordering me to relax. I tried to shrug him off, but he was stronger than me. And it only got worse when I got older.