(aeronautics) Any aerodynamic effects occurring due to a vehicle's body or appendages moving in close proximity to the ground.

(sciences) A side-effect, especially a negative one in pharmacology.

(computing, software) The replacement, by a spell checker, of words that it interprets as being misspelled, by words which are still incorrect in context.

A phenomenon in which attempting to suppress an item of information attracts even more unwanted attention, thus furthering its dissemination.

(Britain) A secondary, often unintended effect; a repercussion, chain reaction.

The technical notion of sensitive dependence on initial conditions in chaos theory.

The property of being cost-effective.

(physics) The energy of a heterogeneous (polychromatic) photon beam calculated as if it were monochromatic

Returning a benefit that justifies the initial investment; economical.

The situation where a widely publicized suicide leads to a number of copycat suicides.