Creet doesn't have a meaning in English. It goes back to its Latin roots.
Discrete came from the Latin discretus.
Discretus came from the Latin discerno.
From dis- (“asunder, in pieces, apart, in two”) + cernō (“see,
discern”).
Here's a list of words derived from cerno:
certain, concern, crime, criminal, decree, discern, discernible,
discernment, discreet, discrete, discretion, discretionary,
discriminant, discriminate, discrimination, discriminative, excrement,
excreta, excrescent, excrete, excretion, excretory, indiscernible,
secret, secretary, secretion, secretive, secretory