foolish

Heedless is a related term of foolish.

As adjectives the difference between heedless and foolish

is that heedless is unaware, without noticing while foolish is lacking good sense or judgement; unwise.

Flimsy is a synonym of foolish.

As adjectives the difference between flimsy and foolish

is that flimsy is likely to bend or break under pressure; weak, shaky, flexible, or fragile while foolish is lacking good sense or judgement; unwise.

As a noun flimsy

is thin typing paper used to make multiple copies.

Foolish is a related term of incongruous.

As adjectives the difference between foolish and incongruous

is that foolish is lacking good sense or judgement; unwise while incongruous is not similar or congruent; not matching or fitting in.

As adjectives the difference between obdurate and foolish

is that obdurate is stubbornly persistent, generally in wrongdoing; refusing to reform or repent while foolish is lacking good sense or judgement; unwise.

Witless is a related term of foolish.

As adjectives the difference between witless and foolish

is that witless is destitute of wit or understanding; wanting thought; hence, indiscreet; not under the guidance of judgment while foolish is lacking good sense or judgement; unwise.

Foolish is a synonym of contemptible.

As adjectives the difference between foolish and contemptible

is that foolish is lacking good sense or judgement; unwise while contemptible is deserving contempt.

As adjectives the difference between innocent and foolish

is that innocent is free from guilt, sin, or immorality while foolish is lacking good sense or judgement; unwise.

As a noun innocent

is those who are innocent; young children.

As adjectives the difference between commonsense and foolish

is that commonsense is exhibiting or using common sense while foolish is lacking good sense or judgement; unwise.

As adjectives the difference between foolish and cowardly

is that foolish is lacking good sense or judgement; unwise while cowardly is showing cowardice; lacking in courage; basely or weakly fearful.

As an adverb cowardly is

in the manner of a coward.

As adjectives the difference between ludicrous and foolish

is that ludicrous is idiotic or unthinkable, often to the point of being funny while foolish is lacking good sense or judgement; unwise.