glower at (someone or something)
To look at someone or something with anger or disapproval. She won't come out and say it, but I can tell she's angry by the way she's glowering at me. Julian glowered at his car when it failed to start.
glower at someone or something
to scowl intently at someone or something. The judge glowered at the irate witness until order was restored. Fred glowered at the painting of his uncle, hating the subject of the picture.