The difference between Defect and Stumble

When used as nouns, defect means a fault or malfunction, whereas stumble means a fall, trip or substantial misstep.

When used as verbs, defect means to abandon or turn against, whereas stumble means to trip or fall.

check bellow for the other definitions of Defect and Stumble

Defect as a noun:

A fault or malfunction.

Examples:

"a defect in the ear or eye; a defect in timber or iron; a defect of memory or judgment"
Defect as a noun:

The quantity or amount by which anything falls short.
Defect as a noun (math):

A part by which a figure or quantity is wanting or deficient.

Defect as a verb (intransitive):

To abandon or turn against; to cease or change one's loyalty, especially from a military organisation or political party.
Defect as a verb (military):

To desert one's army, to flee from combat.
Defect as a verb (military):

To join the enemy army.
Defect as a verb (law):

To flee one's country and seek asylum.

Stumble as a verb (intransitive):

To trip or fall; to walk clumsily.

Examples:

"He stumbled over a rock."
Stumble as a verb (intransitive):

To make a mistake or have trouble.

Examples:

"I always stumble over verbs in Spanish."
Stumble as a verb (transitive):

To cause to stumble or trip.
Stumble as a verb (transitive, figurative):

To mislead; to confound; to cause to err or to fall.
Stumble as a verb:

To strike or happen (upon a person or thing) without design; to fall or light by chance; with on, upon, or against.