The difference between Proper and Upright

When used as adverbs, proper means properly, whereas upright means in or into an upright position.

When used as adjectives, proper means suited or acceptable to the purpose or circumstances, whereas upright means vertical.

Upright is also noun with the meaning: any vertical part of a structure, especially one of the goal posts in sports.

Upright is also verb with the meaning: to set upright or stand back up (something that has fallen).

check bellow for the other definitions of Proper and Upright

Proper as an adjective:

Suitable. Suited or acceptable to the purpose or circumstances; fit, suitable. Following the established standards of behavior or manners; correct or decorous.

Examples:

"the proper time to plant potatoes"

"a very proper young lady"
Proper as an adjective:

Possessed, related. Used to designate a particular person, place, or thing. Proper nouns are usually written with an initial capital letter. Pertaining exclusively to a specific thing or person; particular. In the strict sense; within the strict definition or core (of a specified place, taxonomic order, idea, etc). Belonging to oneself or itself; own. Portrayed in natural or usual coloration, as opposed to conventional tinctures. Being strictly part of some other (not necessarily explicitly mentioned, but of definitional importance) thing, and not being the thing itself. Eigen-; designating a function or value which is an eigenfunction or eigenvalue.

Examples:

"usex [[proper subset]] — [[proper ideal]]"
Proper as an adjective:

Accurate, strictly applied. Excellent, of high quality; such as the specific person or thing should ideally be. (Now often merged with later senses.) Attractive, elegant. In the very strictest sense of the word. Utter, complete.

Examples:

"Now that was a proper breakfast."

"When I realized I was wearing my shirt inside out, I felt a proper fool."

Proper as an adverb (UK, colloquial):

properly; thoroughly; completely
Proper as an adverb (nonstandard, colloquial):

properly

Upright as an adjective:

Vertical; erect.

Examples:

"I was standing upright, waiting for my orders."
Upright as an adjective:

Greater in height than breadth.
Upright as an adjective (figuratively):

Of good morals; practicing ethical values.
Upright as an adjective (of a [[golf club]]):

Having the head approximately at a right angle with the shaft.

Upright as a noun:

Any vertical part of a structure, especially one of the goal posts in sports.
Upright as a noun:

A word clued by the successive initial, middle, or final letters of the cross-lights in a double acrostic or triple acrostic.
Upright as a noun (informal):

An upright piano.
Upright as a noun:

Short for upright vacuum cleaner.

Upright as a verb (transitive):

To set upright or stand back up (something that has fallen).