Quite 'respectable' words can become abused over time....

for example..

'The word 'spastic' is used differently depending on location which has led to some controversy and misunderstanding.

The term generally originates from spasticity, a medical condition characterised by hypertonia, or a high degree of muscle tightness.

Spasticity underlies spastic diplegia and many other forms of cerebral palsy. But the word in common speech can also be used in a pejorative context.

The level of severity depends on whether one understands it as it is used in the United States or the United Kingdom . Wikipedia

In the UK it can be considered highly abusive and taboo

"You spaz" became popular insults amongst children and in 1994 The Spastics society, a well known UK charity, changed its name.

check out Worst word vote from the BBC 'Ouch' site and a comment on the film from the same site