The difference between Blunder and Lapse

When used as nouns, blunder means a clumsy or embarrassing mistake, whereas lapse means a temporary failure.

When used as verbs, blunder means to make a clumsy or stupid mistake, whereas lapse means to fall away gradually.

check bellow for the other definitions of Blunder and Lapse

Blunder as a verb (intransitive):

To make a clumsy or stupid mistake.

Examples:

"to blunder in preparing a medical prescription"
Blunder as a verb (intransitive):

To move blindly or clumsily.
Blunder as a verb (transitive):

To cause to make a mistake.
Blunder as a verb (transitive):

To do or treat in a blundering manner; to confuse.

Lapse as a noun:

A temporary failure; a slip.
Lapse as a noun:

A decline or fall in standards.
Lapse as a noun:

A pause in continuity.
Lapse as a noun:

An interval of time between events.
Lapse as a noun:

A termination of a right etc., through disuse or neglect.
Lapse as a noun (meteorology):

A marked decrease in air temperature with increasing altitude because the ground is warmer than the surrounding air.
Lapse as a noun (legal):

A common-law rule that if the person to whom property is willed were to die before the testator, then the gift would be ineffective.
Lapse as a noun (theology):

A fall or apostasy.

Lapse as a verb (intransitive):

To fall away gradually; to subside.
Lapse as a verb (intransitive):

To fall into error or heresy.
Lapse as a verb:

To slip into a bad habit that one is trying to avoid.
Lapse as a verb (intransitive):

To become void.
Lapse as a verb:

To fall or pass from one proprietor to another, or from the original destination, by the omission, negligence, or failure of somebody, such as a patron or legatee.