discriminate against (someone or something)
To impose limitations on a particular person or group for prejudicial reasons. Those who continue to discriminate against people of color will continue to meet resistance from those who believe in equality.
discriminate between (someone or something)
To recognize the differences between people or things. I have a hard time discriminating between Jim and Greg, but they are identical twins after all. You can discriminate between hydrangea and phlox by looking at their leaves.
discriminate against someone or something
to single out a type of person or thing for special negative treatment or denial of equal treatment; to act in a prejudicial manner against someone or something. This law discriminates against short people. You discriminate against people in wheelchairs.
discriminate between
someone and someone else or something and something else to distinguish between people or between things. I find it hard these days to discriminate between my friends and my enemies. Can you discriminate between this shade of pink and that one?