inept

As a noun idiot

is (slang|derogatory) a proponent of intelligent design.

As an adjective inept is

not able to do something; not proficient; displaying incompetence.

As adjectives the difference between inept and feckless

is that inept is not able to do something; not proficient; displaying incompetence while feckless is lacking purpose.

As adjectives the difference between gauche and inept

is that gauche is awkward or lacking in social graces; bumbling while inept is not able to do something; not proficient; displaying incompetence.

As adjectives the difference between inept and competent

is that inept is not able to do something; not proficient; displaying incompetence while competent is having sufficient skill, knowledge, ability, or qualifications.

As adjectives the difference between inept and messy

is that inept is not able to do something; not proficient; displaying incompetence while messy is in a disorderly state; chaotic; disorderly.

As adjectives the difference between inept and slovenly

is that inept is not able to do something; not proficient; displaying incompetence while slovenly is having an untidy appearance; unkempt.

As adjectives the difference between inept and shiftless

is that inept is not able to do something; not proficient; displaying incompetence while shiftless is lazy, unmotivated.

As adjectives the difference between adroit and inept

is that adroit is dexterous, deft or skillful while inept is not able to do something; not proficient; displaying incompetence.

As adjectives the difference between inept and indolent

is that inept is not able to do something; not proficient; displaying incompetence while indolent is habitually]] lazy, [[procrastinate|procrastinating, or resistant to physical labor/labour.

Fruitless is a synonym of inept.

As adjectives the difference between fruitless and inept

is that fruitless is useless; unproductive while inept is not able to do something; not proficient; displaying incompetence.