ingenuous
showing childlike simplicity; innocent
Remember these words this way: Ingenious has an i, like genius, and it also
expresses the main qualities of genius.
Baby geniuses frequently discover ingenious ideas in ingenuous ways. (It also
helps if you know that disingenuous means “crafty,” not innocent or
straightforward.)
innate
belonging to someone from birth; inherent
The malice in Nate is innate. He’s been nasty since birth.
insatiable
impossible to satisfy
You must develop an insatiable desire to learn more and more vocabulary words.
inscrutable
enigmatic; difficult to understand
The Swedish furniture manufacturer’s instructions on how to unscrew the table
were inscrutable.
insipid
lacking excitement; vapid
The insipid innkeeper stayed in, sipped wine, and slept.
intangible
not perceptible to the touch; impalpable
You can’t touch the tangent of π/2; it’s intangible.
intrinsic
natural; innate; inherent
I have an intrinsic love of travel, but I always get train-sick.