state of emergency (unusually difficult or dangerous situation)

a machine, a device; a contraption / a loom / an opportunity, a chance to do something; the right time or moment / something of great importance: the linchpin of the matter

indicates aircraft / indicates paper aeroplanes / indicates lives in video games

indicates machines / indicates airplanes

a trap or snare that works by beheading the bird or beast caught in it

manipulation (as in a device) / manipulation (as in a person): deception, taking someone in / getting on someone's right side; humoring someone; an effort to please someone

mechanism / machine / airplane / opportunity

(arithmetic) arithmetic operation

(mathematics, computing) A function or other mapping that carries variables defined on a domain into another variable; operator.

(set theory) set operation