1.slender or fine, as a fiber
2.thin in consistency; rare or rarefied.
3.lacking in clarity; vague
4.rare, as air at high altitudes; not dense
attenuated,insignificant, unimportant, trivial, trifling.
He gave a rather tenuous account of his past life.
The policeman had a a tenuous argument with the thief.
Ram holds a tenuous position in history.