Wiktionary
n. 1 (context literally English) The wave produced by a hand. 2 A glib statement or explanation that glosses over important details. vb. (context rhetoric academia English) To explain something superficially, skipping over important details, perhaps appealing to intuition instead.
Usage examples of "handwave".
And if he read the handwave correctly, the galago was probably listening at the window.
What they had to work with was more in the nature of handwaving and colored smokes than real weaponry or the skill to use it—but to the repair crews of a DSR, handwaving and colored smokes were second nature.
These Guardian guys existed, after all, and some, or maybe even most, of what they did was handwaving and persuasion, just as it had been in Andrew's case.
The gesture meant no more to him than his handwaving at the horned beast did to her.
Now she watched as the argument progressed, with handwaving and headshaking and—by the expressions—raised voices.