If something is tenuous it's thin, either literally or metaphorically. If you try to learn a complicated mathematical concept by cramming for 45 minutes, you will have a tenuous grasp of that concept, at best.

Tenuous comes from the Latin word tenuis, for thin, and is related to our word tender. Something can be physically tenuous, like a spiderweb or ice on a pond. We more often use it in a metaphorical sense, to talk about weak ideas. Tenuous arguments won't win any debate tournaments. Synonyms for tenuous, also used physically or metaphorically, are flimsy and shaky.

Definitions of tenuous

adj very thin in gauge or diameter

“a tenuous thread”
of relatively small extent from one surface to the opposite or in cross section

adj having thin consistency

“a tenuous fluid”
relatively thin in consistency or low in density; not viscous

adj lacking substance or significance

“a tenuous argument”
flimsy, fragile, slight, thin
insignificant, unimportant
devoid of importance, meaning, or force

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.