There are 64 words ending in -gh in English. Of these, 27 are compounds:
Of the remaining 37, 6 are loanwords, mostly from Irish:
inveigh is an irregular loan; the form *invey would be expected, but it was spelt with a -gh, possibly under influence of weigh.
The remaining 31 native roots ending in -gh, sorted by ending:
There are also 542 words with gh in a non-terminal position (Including one already listed: thigh-high). Of these, [TODO]
If you want to suffer pronunciation whiplash, try reading this (very poorly written, but hopefully gets the idea across) poem aloud to yourself (made from all but 3 -ough words):
once in a tree, sat a lonely chough wanderlusty, he flew from his bough he flew far and further, but never enough then at a farm, he landed on a plough you see, this creature's had it rough all he wants is to make a little dough sure, he may still act quite though that doesn't mean he isn't tired, though he is simply endeavoring to be completely thorough so that he may one day return to his native borough← back