The difference between Lousy and Slight

When used as adjectives, lousy means remarkably bad, whereas slight means small in amount, gentle, or weak.

Slight is also noun with the meaning: the act of slighting.

Slight is also verb with the meaning: to treat as slight or not worthy of attention.

check bellow for the other definitions of Lousy and Slight

Lousy as an adjective:

Remarkably bad; of poor quality, dirty, or underhanded; mean, contemptible.

Examples:

"No offense, but his cooking is lousy''."

"synonyms: miserable"
Lousy as an adjective:

Infested with lice.
Lousy as an adjective (colloquial, usually with ''with''):

Filled or packed (with something, usually bad).

Examples:

"The place was lousy with students''."

"synonyms: inundated jam-packed teeming"

Slight as an adjective:

Small in amount, gentle, or weak; inconsiderable; unimportant; insignificant; not severe.

Examples:

"a slight (i.e. feeble) effort; a slight (i.e. not deep) impression; a slight (i.e. not convincing) argument; a slight (i.e. not thorough) examination; a slight (i.e. not severe) pain; in the slight future (i.e. the very [[near]] future)"
Slight as an adjective:

Not stout or heavy; slender.

Examples:

"a slight but graceful woman"
Slight as an adjective (regional):

Even, smooth or level; still (of the sea).

Examples:

"A slight stone"

"The sea was slight and calm"
Slight as an adjective (obsolete):

Foolish; silly; weak in intellect.

Examples:

"rfquotek Hudibras"
Slight as an adjective (regional, obsolete):

Bad, of poor quality (as goods).

Examples:

"A gullible chapman was fooled into buying really slight goods."
Slight as an adjective (dated):

Slighting; treating with disdain.

Slight as a verb (transitive):

To treat as slight or not worthy of attention; to make light of.
Slight as a verb (transitive):

To give lesser weight or importance to.
Slight as a verb (transitive):

To treat with disdain or neglect, usually out of prejudice, hatred, or jealousy; to ignore disrespectfully.
Slight as a verb (intransitive):

To act negligently or carelessly.
Slight as a verb (transitive, military, of a fortification):

To render no longer defensible by full or partial demolition.

Examples:

"rfquotek Clarendon"
Slight as a verb (transitive):

To make even or level.

Examples:

"rfquotek Hexham"
Slight as a verb (transitive):

To throw heedlessly.

Slight as a noun:

The act of slighting; a deliberate act of neglect or discourtesy.
Slight as a noun (obsolete):

Sleight.

Examples:

"rfquotek Edmund Spenser"