"abrupt appearance" is a correct and usable phrase in written English.
You can use it to refer to a sudden, unexpected appearance, such as when someone appears in a room without warning. For example, "The CEO made an abrupt appearance in the boardroom, catching everyone by surprise."
This time, our rather more abrupt appearance disclosed no basking seals.
"The Continuous Life" continues after death, whose abrupt appearance, breaking up the party, Strand often described.
One prominent researcher is putting forward a new hypothesis of genetic change to explain a more recent and abrupt appearance of creativity.
One of the most memorable moments of the Obama Presidency was his abrupt appearance on nationwide television, shortly before midnight, on Sunday, May 1 , 2011
Whatever the reason for their abrupt appearance, the increasing number of the videos online has not coincided with any break in the violence on the ground in Syria.
Walcott's discovery was further evidence of the so-called Cambrian Explosion — the apparently abrupt appearance of complex animals in the fossil record within the Cambrian Period, from about 542 to 490 million years ago.
Simpson devised his own special blend of "evolutionary determinants" to account for the rapid evolution underlying the abrupt appearances of new, higher taxa.
That's ultimately what it boils down to, when you really think about what happened with the legendary comedian during his abrupt, awkward appearance on SNL 40 on Sunday.
However, we removed the first 2 s of each recording from analysis to avoid any potential effect of the abrupt stimulus appearance on subjects' postural sway.
Varus thrust is defined as the visualized dynamic bowing-out of the knee laterally (i.e. the abrupt first appearance of varus) while the limb is in the weight-bearing (stance) phase of gait, followed by the return to a less varus alignment during the non- weight-bearing (swing) phase of gait.
For them, the essence of thinking lay in sudden perceptual restructuring or reorganization, akin to the abrupt changes in appearance of an ambiguous visual figure.
