Sexual conflict is a term in evolutionary biology. It occurs in a species when what benefits the females is different from what benefits the males.
The word 'benefit' here means 'what benefits the reproduction of the female's (or male's) genes. It is expressed as a difference in biological fitness.
The conflict can lead to an evolutionary arms race between males and females. It has primarily been studied in animals, though it can in principle apply to any sexually reproducing organism, such as plants and fungi.