stumbling blockˈstumbling ˌblock noun [countable] 
Examples
The main stumbling block to starting new research is that we lack qualified people.
ExamplesEXAMPLES FROM THE CORPUS
Thesaurus- In the autumn of 1987, Conran ran into a potentially more serious stumbling block to his plans.
- It is still foolishness and a stumbling block.
- Only rarely is the lack of sufficient minimum capability a real stumbling block to change.
- The stumbling block is a case challenging the constitutionality of the new law.
- They needed the scrupulous professional integrity which nearly proved such a stumbling block to them in this case.
Longman Language Activatora problem that stops you from making progress► setback
a problem or difficulty that stops you from achieving somethingstumbling block to something that happens which stops you making progress or which makes things worse than they were before: · Arafat has survived crises, setbacks, and challenges to his leadership.have/suffer a setback: · The peace talks have suffered a series of setbacks.setback for: · The court's decision was a major setback for Bradley.setback in: · Manning suffered a setback in his battle against alcoholism.serious/major/big setback: · The two losses are a serious setback for the team's playoff hopes.political/economic/legal etc setback: · The decision is a legal setback for the steel company.business/election etc setback: · He had been depressed over a number of business setbacks.
► hurdle a problem or difficulty that must be dealt with before you can do or achieve something else: · The main hurdle at present is getting the council's permission.legal/bureaucratic/political etc hurdle: · Women face a lot of legal hurdles trying to prove sexual harassment.· There are lots of bureaucratic hurdles to deal with when adopting a child.hurdle for: · Requiring school uniforms can be a financial hurdle for the poor.clear/pass a hurdle: · The bill has cleared all the hurdles before it and will soon become law.
► stumbling block a fact or situation that will make it very difficult for something to be achieved: · Negotiations with management broke off Tuesday, with wage proposals the stumbling block.stumbling block to: · Each side has accused the others of creating stumbling blocks to peace.stumbling block for: · Mortgage interest rates have fallen, but large down payments remain a stumbling block for house buyers.
► hindrance something that makes it very difficult for you to do what you are trying to do: · America's top golfers played well despite the hindrance of early morning mist.· I concentrated on my career, feeling that a family would be a hindrance.be a hindrance to: · The country's poor infrastructure is a major hindrance to importers.· The biggest hindrance to economic reform has been the lack of access to U.S. markets.without hindrance: · Travelers can move through the country without hindrance.more of a hindrance than a help (=causing more problems than there would be otherwise): · The girls wanted to set the table, but they were more of a hindrance than a help.
► obstacle a difficult problem that stops someone or something making progress or developing: · The deal should go through, but there are several legal obstacles to overcome first.· There are a number of obstacles in the way of a lasting peace settlement.obstacle to: · There's no reason why the fact of being a parent should be an obstacle to women's career progression.
The main stumbling block to starting new research is that we lack qualified people.