Difference between Impious and Irreligious

IMPIOUS vs IRRELIGIOUS: ADJECTIVE

Lacking piety and reverence for a god
Lacking due respect or dutifulness
Lacking reverence; not pious.
Not pious; wanting piety; irreligious; irreverent; ungodly; profane; wanting in reverence for the Supreme Being
Not pious
Lacking piety or reverence for a god
Lacking reverence or respect, especially towards a god

Hostile or indifferent to religion
Destitute of religion; not controlled by religious motives or principles; ungodly. Cf. Impious.
Indicating a lack of religion; profane; wicked.
Contrary to religious beliefs and practices.
Describing a conscious rejection of religion.
Having no relation to religion; non-religious.

Not pious; lacking piety or reverence for God; irreligious; profane; wicked.
Characterized by want of piety; of an irreverent or wicked character: as, an impious deed; impious writings.
Synonyms Unrighteous, Profane, etc. See irreligious.

Synonyms Irreligious, Godless, Ungodly, Unrighteous, Impious, Profane, Atheistic, are words expressing the position or conduct of those who deny the existence of a God or refuse to obey his commandments. Irreligious means destitute of religion as a principle, contemning religion and not checked by its restraints; godless, acknowledging no God, disregarding God and therefore his commandments, sinful, wicked; ungodly, essentially the same as godless, but stronger as to both feeling and action; unrighteous, disregarding right, contrary to right and by implication (right being with this word viewed chiefly as the personal will of God) not only wrong or unjust, but sinful; impious, irreverent or contemptuous toward God, defiant or wanton in irreligion; profane, impious by word or deed, irreverent or blasphemous; atheistic, holding the doctrine of the non-existence of a God (applied, on account, of the natural tendency of men to deny the existence of a God where their spirit or manner of life is condemned by the teachings of the Christian religion, to whatever would be thus condemned or whoever thus denies). See atheous, 2.
Profane; wicked: as, irreligious conduct.
Not religious; without religious principles; contemning religion; impious; ungodly.

Contemptible, Unworthy, Unrighteous, Detestable, Immoral, Licentious, Pious, Sinful, Unholy, Undutiful, Irreverent, Disrespectful, Ungodly, Godless, Irreligious

Unchristian, Religionist, Godless, Unreligious, Heathenish, Nonchurchgoing, Atheistical, Lapsed, Ungodly, Unbelieving, Nonobservant, Heathen, Pagan, Impious, Atheistic

Contemptible, Unworthy, Unrighteous, Detestable, Immoral, Licentious, Pious, Sinful, Unholy, Undutiful, Irreverent, Disrespectful, Ungodly, Godless, Irreligious

Unchristian, Religionist, Godless, Unreligious, Nonchurchgoing, Heathenish, Atheistical, Lapsed, Ungodly, Unbelieving, Nonobservant, Heathen, Pagan, Impious, Atheistic

Condemn yourself, because you, the impious and infamous reigns of Jehoram Ahaziah.
Maimonides thinks that this view is common, vulgar, stupid, and impious.
Nineveh, that exceeding great city, with its vast but impious population.
But for you, the impious, there will be a curse.
Specifically, impious and reproachful speech injurious to the divine majesty.
But a child had witnessed their impious and criminal action.
Let vengeance now be sated on impious, cruel foes!
Prosperity inclines sinners to an impious neglect of God.
Unhappy Dido, now you think of impious deeds?
Son of God would be killed for the impious; but in the present it is announced that He has been killed for the impious.

Your husband is not an idle loafer or engaged in an irreligious occupation.
Its religious aspect was Methodistic, and its irreligious side rather coarse.
For right or wrong, irreligious people celebrate Christmas and have successfully cleaved Christ from the celebrations.
The remaining population is either irreligious or belongs to other religious groups.
Religiousness as predictor of confidence in religious and irreligious institutions.
Many of us live among the unchurched, uncivilized and irreligious.
In America, even irreligious Jews still embrace this initiation rite.
Why should the irreligious be expected to do more?
Would a devotional time benefit an irreligious person?
None but an irreligious man would think that.