Beggar-my-neighbour is a term used to describe a situation where one party benefits at the expense of the other. Synonyms for this phrase include 'zero-sum game', 'winner takes all', 'cut-throat competition', and 'survival of the fittest'. These phrases all convey the idea that success is achieved through the downfall of others, and that there are no shared benefits. Other similar expressions include 'dog eat dog', 'devil take the hindmost', and 'every man for himself'. While these phrases may accurately describe competitive situations, it is important to remember that cooperation and collaboration can often result in mutual gains rather than a zero-sum outcome.