The phrase "discreet glance" is correct and can be used in written English.
You can use it when you want to describe a glance that is meant to be subtle or covert. Example sentence: He sent her a discreet glance to let her know that it was time to leave.
Perhaps there was a reason for Tomas Maier, that most discreet and thoughtful of designers, to open his Bottega Veneta collection with what looked at first glance to be slender 1940s dresses.
We've gotten a few discreet glances as what could be RIM's first next-generation BlackBerry in the past, and now we may have a name to go with it.
From discreet glances at the opera to wolf-whistles at a construction site, the urge to ogle women has been a part of the male psyche since the time some ancient ancestor first glanced up from his spear-making to watch a comely lass wander by.
Brief, discreet glances are the key to flirting with your eyes.
On the other hand, it might be amusing to imagine Agatha Christie conjuring with a Nora Roberts sex scene, since erotic tension, if it exists at all in Christie's mysteries, is most commonly manifested in a furtive glance... or a discreet little fumbling with a hat or glove.
With the smallest gestures -- the tilt of his body, the lift of a hand, a quickly shuttered glance -- he conveys his intense but discreet yearning for the woman who ultimately refuses him.
A discreet stash of signatures on the print, barely legible at a glance, brings this image into the upper stratosphere of automotive collectibles.
Wearing one allows subway riders an easy, and discreet, way of checking the sequence of stops — it takes only a glance at your wrist.
The lovers exchange smoldering glances as they pass on horseback, and soon enough Alejandra is sneaking into John Grady's quarters for a bit of discreet montage.
