Answer:
It depends on how you're using the word, but here are a few.
"My husband and I had a tenuous argument this morning."
"My sweater was made out of tenuous thread, so it ripped when caught on the door knob."
"A tenuous fluid is on the ground."
There are three ways that you can use the word tenuous.
1. insignificant or flimsy (see example #1)
2. slim, fine or delicate (see example #2)
3. diluted or rarefied in consistency or density (see #3)