Something that happens in the
plot that is highly unlikely to happen, though still technically possible.
Different from plot
hole as a plot
hole is something that should be impossible to happen.
A scene featuring
Q giving
007 his gadgets is a staple of James Bond films.
Now imagine if the film did not feature this and we see
007 using a never-before-seen gadget to get out of a
tight situation. This would be a plot contrivance, as the audience would have zero reason to believe that 007 would have a gadget of this kind, though him having this gadget is still technically not impossible, preventing it from being a plot hole.