"Leaning on" means resting your weight against something for support. It can also mean relying on someone or something for help, or pressuring someone to act.
She wasn't doing a thing that I could see, except standing there leaning on the balcony railing, holding the universe together. J. D. Salinger
To those leaning on the sustaining infinite, today is big with blessings. Mary Baker Eddy
It is time we in Scotland put England in its proper place and instead of our leaning on England and taking inspiration from her, we should lean and turn to Europe, for it is there our future prosperity lies. Hugh MacDiarmid
And through it all, calm and impassive, leaning on his elbow and gazing down, Wolf Larsen seemed lost in a great curiosity. This wild stirring of yeasty life, this terrific revolt and defiance of matter that moved, perplexed and interested him. Jack London
Men, knowing not how to handle the tool of the mind, have become used to leaning on others and on habit; and, owing to that, this splendid tool, the human mind, has in fact become unreliable through neglect. Nyanaponika Thera
I bought a piano once because I had the dream of playing As Time Goes By as some girl's leaning on it drinking a martini. Great image. But none of it worked out. I can't even play Chopsticks. But I've got a nice piano at my house! George Clooney