Definition of "Tense" :

noun: a grammatical category of verbs used to express distinctions of time

verb: cause to be tense and uneasy or nervous or anxious

"He got a phone call from his lawyer that tensed him up."

verb: become tense, nervous, or uneasy

"He tensed up when he saw his opponent enter the room."

verb: increase the tension on

"Alternately relax and tense your calf muscle."

verb: become stretched or tense or taut

"The bodybuilder's neck muscles tensed."

adjective: taut or rigid; stretched tight

"Tense piano strings."

adjective: pronounced with relatively tense tongue muscles (e.g., the vowel sound in beat')

adjective: in or of a state of physical or nervous tension