hypertonia

https://doi.org/10.1351/goldbook.11820
Extreme tension of the muscles or arteries.
Note: This is often a result of an upper motor neuron lesion in the brain, which is accompanied by decreased synaptic inhibition and increased excitability of muscle.
Source:
PAC, 2015, 87, 841. (IUPAC Glossary of terms used in neurotoxicology (IUPAC Recommendations 2015)) on page 874 [Terms] [Paper]