Condone - condemn

These verbs sound similar, and they are often found in similar contexts. But their meanings are so different as to be virtually opposite.

• The basic meaning of 'to condemn' is 'to find guilty [in a court of law]'. The meaning has expanded, so that a ship that is unfit for the sea can be condemned by a surveyor, or a piece of woodwork written off as riddled with woodworm or dry rot: it must be destroyed and replaced. In a rather more general way, condemn is used to mean 'disapproved of': "the Opposition condemned the Government's policy towards France."
• The basic meaning of 'to condone' is 'to forgive', or "To forgive or overlook (an offence), so as to treat it as non-existent" (OED). It is a term in Law, particularly that of the Church and of marriage. More loosely, it means 'to tolerate', and can be used in ordinary life to mean 'to turn a blind eye to' or 'to wink at' some irregular behaviour. The petty theft of some stationery is condoned in many offices.