strain

Dictionary definition · strain

(physics) deformation of a physical body under the action of applied forces
difficulty that causes worry or emotional tension"she endured the stresses and strains of life"
a succession of notes forming a distinctive sequence"she was humming an air from Beethoven"
(psychology) nervousness resulting from mental stress"his responsibilities were a constant strain"
a special variety of domesticated animals within a species"he experimented on a particular breed of white rats"
(biology) a group of organisms within a species that differ in trivial ways from similar groups"a new strain of microorganisms"

to exert much effort or energy"straining our ears to hear"
test the limits of"You are trying my patience!"
use to the utmost; exert vigorously or to full capacity"He really extended himself when he climbed Kilimanjaro"
separate by passing through a sieve or other straining device to separate out coarser elements"sift the flour"
cause to be tense and uneasy or nervous or anxious"he got a phone call from his lawyer that tensed him up"
become stretched or tense or taut"the bodybuilder's neck muscles tensed"

Source: Open English WordNet (CC BY 4.0).