The maxim de minimis non curat lex actually means that the law does not take any account of the trivial matters .

The principle underlying the maxim is that nothing is a wrong which is trivial in nature and a person of ordinary sense and temper would not complain . This maxim protects a trivial wrong though infringes legal right of other . But the maxim does not protect a wrongdoer when the wrong is not trivial in nature and a harm is caused or a legal right is infringed .
This principle is also recognized in section 95 of the Indian Penal Code .

An example will make it clear .

X is driving along a dusty road at a good speed , and the wheels of his motor car throw a little dust on the clothes of Y , a pedestrian . Here X is not liable for tort , on the basis of the maxim de minimis non curat lex , as the matter is trivial in nature .

Another interesting example may make it more clear .

X walks on through the Y’s land , without Y’s permission , only for first time , without causing damage to the land of Y . If for once , then it is trivial matter ,and the maxim would protect him , but if X repeats again and again to establish his right of way upon the Y’s land then it does not remain a trivial matter and it becomes a tort and the maxim would not then protect X .

In the leading case of Coward Vs. Baddeley , a by-stander touched a fireman on the arm to attract his attention to another part of a building where a fire was raging . On a suit filed by the fireman for battery , the Court held that the by-stander was not liable for battery on the basis of maxim de minimis non curat lex .