The difference between Lovely and Pretty

When used as nouns, lovely means an attractive, lovely person, especially a (professional) beauty, whereas pretty means a pretty person.

When used as adverbs, lovely means in a lovely fashion or manner, whereas pretty means somewhat, fairly, quite.

When used as adjectives, lovely means beautiful, whereas pretty means pleasant in sight or other senses.

Pretty is also verb with the meaning: to make pretty.

check bellow for the other definitions of Lovely and Pretty

Lovely as an adjective:

Beautiful; charming; very pleasing in form, looks, tone, or manner.

Examples:

"It's a lovely day and the sun is shining."

"The music box plays a lovely melody."

"The castle garden enchants visitors with its lovely blooms."
Lovely as an adjective:

Very nice, wonderful.

Examples:

"It would be lovely to have a little more money to spend."
Lovely as an adjective (obsolete):

Inspiring love or friendship; amiable.
Lovely as an adjective (obsolete):

Loving, filled with love.

Lovely as an adverb (informal):

In a lovely fashion or manner; beautifully.

Lovely as a noun (informal):

An attractive, lovely person, especially a (professional) beauty.

Examples:

"a calendar depicting young lovelies in bikinis"
Lovely as a noun:

Examples:

"Goodbye, my lovely."
Lovely as a noun:

A lovely object.

Pretty as an adjective:

Pleasant in sight or other senses; attractive, especially of women or children.
Pretty as an adjective:

Of objects or things: nice-looking, appealing.
Pretty as an adjective (often, _, pejorative):

Fine-looking; only superficially attractive; initially appealing but having little substance; see petty.
Pretty as an adjective:

Cunning; clever, skilful.
Pretty as an adjective (dated):

Moderately large; considerable.
Pretty as an adjective (dated):

Excellent, commendable, pleasing; fitting or proper (of actions, thoughts etc.).
Pretty as an adjective (ironic):

Awkward, unpleasant.

Pretty as an adverb:

Somewhat, fairly, quite; sometimes also (by meiosis) very.
Pretty as an adverb (dialect):

Prettily, in a pretty manner.

Pretty as a noun:

A pretty person; a term of address to a pretty person.
Pretty as a noun:

Something that is pretty.

Examples:

"We'll stop at the knife store a look at the sharp pretties."