This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. The characteristic of being tense.

n. A particular vowel or consonant quality that is phonemically contrastive in many languages, including English.

n. The state of being tense, or stretched to stiffness; stiffness; rigidness.

n. the physical condition of being stretched or strained

n. (psychology) a state of mental or emotional strain or suspense

"NBC's Chuck Todd says there's a 'tenseness' between John and Sarah (More Pravda Propaganda)"

tightness    tighten    excitability    irascibility    nervousness    orderliness    psychoneurosis    vomit    slipperiness    discomposure