tenuous

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
1

adj very thin in gauge or diameter

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

adj having thin consistency

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

adj lacking substance or significance

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