Ribald evolved into Middle English (as a noun denoting a lowly retainer or a licentious or irreverent person): from Old French ribauld, from riber ‘indulge in licentious pleasures’, from a Germanic base meaning ‘prostitute’.

Ribald is marked by coarseness or lewdness : crude, offensive. ribald language. ribald humor. 2. : characterized by or using coarse, indecent humor. 

The earliest known use of "ribald" in English is from before 1250, during the Middle English period, in the text "Wohunge ure Lauerd". 

Some common synonyms of ribald are coarse, gross, obscene, and vulgar. While all these words mean "offensive to good taste or morals," ribald applies to what is amusingly or picturesquely vulgar or irreverent or mildly indecent.

Examples of ribald in a sentence: 
The result has often been gleefully, hilariously ribald.  
There may have been some who might have scolded a former president for – gasp – daring to indulge in ribald, low-brow swipes.
The whole House burst "into ribald laughter at this quite unexpected solution of the problem of a better central control of our war effort."

Examples of ribald humor in Romeo and Juliet by William Shakespeare 
In Act 2, Scene 1, Mercutio humorously mocks Romeo's infatuation with Rosaline, unaware of his love for Juliet, using ribald jokes. Act 2, Scene 4 features Mercutio's witty exchanges with Romeo and the Nurse, filled with puns and sarcasm. Throughout the play, comedic moments, such as the Nurse's ribald anecdotes and the servants' antics, balance the drama, highlighting Shakespeare's use of ribald humor within a tragic narrative.

Comedians that used the most ribald in their acts - All Time: 
1.  Lenny Bruce 
2.  Richard Pryor 
3.  George Carlin 
4.  Red Foxx 
5.  Bob Saget 
6.  Andrew Dice Clay
7.  LaWanda Page 
8.  Gilbert Gottfried 
9.  Pearl Williams 
10. Chris Rock 
12. Rodney Dangerfield 
14. Moms Mabley
15. Eddie Murphy
16. Tracy Morgan 
per "Cracked"

Just the facts:

RIBALD Definition & Meaning - Merriam-Webster

1 hour ago, drpaladin said:

Of these, I only saw Redd Foxx live and a month later he was dead. Watching the audience was nearly as amusing as his act. Despite the XXX warning, some were expecting Sanford and Son humor, but it was very ribald.

I saw Moms Mabley in concert once and she was very ribald!