sticking point 
noun
An obstacle to progress towards an agreement or goal: safety issues have been a sticking point in the negotiations...
- The prisoners have become a major sticking point to progress on the US-backed road map peace plan.
- It affords a temporary sticking point in the forward progress of evolution…
- Start the advanced routine only when you hit a sticking point in your general progress.
- microchiropteran
- microcinema
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- microcircuit
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- microcirculation
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- microclastic
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- microclimatological
- microclimatologist
- microclimatology
- microcline
- micrococcal
- micrococcus
- microcode
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- microcoding
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- microcolony
- microcomputer
- microcomputing