Rudimentary vs Underdeveloped - What's the difference?

As adjectives the difference between rudimentary and underdeveloped

is that rudimentary is of or relating to one or more rudiments while underdeveloped is immature and not fully developed.

past tense of underdevelop.

(en adjective)

of or relating to one or more rudiments

I have only a rudimentary grasp of chemistry .

Basic; minimal; with less than, or only the minimum, necessary.

His grasp of rudimentary English allowed him at least to do the shopping .

His rudimentary driving skills meant that he was a danger on the road .

(en adjective)

immature and not fully developed

having a low level of economic productivity and technological sophistication

(photography) of a film that has had insufficient development before being fixed

(head)

(underdevelop)