The word 'merely' is correct and usable in written English. You can use it to express that something is only small or slight in comparison to what is expected. Example sentence: His contribution to the project was merely minimal.
After all, Johnson was surrounded by Kennedy's advisers and always insisted he was merely continuing Kennedy policy.
Thompson's recent comments to that effect which have done so much to inflame political opinion were merely reflecting that view.
Were the system Fifa is proposing to restrict itself merely to offside decisions, or questions of whether a foul took place in or outside the area, it might be quite useful, although one suspects it would soon enough encompass other areas of the game.
It's counterproductive for Wong to insist that it isn't enough for conservative women to merely support the principles of gender equality.
These acts are not merely compatible with liberalism – they are a necessary condition for any society that is free in its culture as well as in its laws and institutions.
Or perhaps they have merely accepted there is no real way to respond to it.
There are plenty of other stories of that nature and, if nothing else, at least the revulsion of Blackpool's fans is not merely restricted to the Fylde coast.
Being a terminologist, I care about word choice. Ludwig simply helps me pick the best words for any translation. Five stars!
Maria Pia Montoro
Terminologist and Q/A Analyst @ Translation Centre for the Bodies of the European Union