In Arabic language, it is known that each name has a meaning, in the dictionary "Lisan Al-'Arab": "Al-Abbas is the lion from which other lions flee, and this is why a man may be called Abbas."
In another dictionary: Al-Abbas and Al-Aboos comes from "frowning" and they are two names of the lion.
And in the dictionary "Muntaha Al-Arb": "Al-Abbas is a characteristic that is said to the brave and very valiant, and it is also a name of the lion. That is why many have described Al-Abbas (peace be upon him) in the battlefields as the angry lion.
It is also said that Al-Abbas means lion, and it is the name of the uncle of the holy Prophet (prayers and Allah's peace be upon him and his holy Household) and the name of the son of Imam Ali (peace be upon him) from his wife Bint Huzam Al-Kilabyah [Um Al-Baneen (peace be upon her)], whom he married after the martyrdom of the Lady Fatima Az-Zahra (peace be upon her). Al-Abbas son of the Commander of the Faithful (peace be upon both of them) was brave, intrepid and attacked the enemies in wars like an angry lion and this is why he was called "Al-Abbas."
And in the book "Al-Muntakhab of Turayhi": "Al-Abbas son of Ali (peace be upon him) is like the great mountain, whose heart is like a strong towering mountain, as he was a brave knight and heroic lion, known by his strength in the field of war.
In another source: "The commander of the Faithful (peace be upon him) gave him the name of "Al-Abbas" as he knew his courage, magnanimity and power, the enemies trembled for fear when Al-Abbas (peace be upon him) was in the battlefield. In wars, he fought the bravest of the enemies and killed them. He always stood up with pride, intrepidity and courage since his childhood until the day of his martyrdom (peace be upon him).
In "Maqatil At-Talibyyin": "Al-Abbas was a handsome man, whenever he rode the most beautiful of the horse, his feet drew a line on the ground. And in another source: "Those who were killed with Imam Al-Hussayn (peace be upon him) were all in the highest degree of courage and the highest ranks of magnanimity,but Al-Abbas son of Ali (peace be upon both of them) had the highest of the highest degrees, and his rank was the most noble as he is one of the lights of of the most brave of humans, a branch of the tree that enlightens the whole universe.
The name of "Al-Abbas" (peace be upon him) was then a thunderbolt over the head of enemies of Islam and humanity wherever they are, whether in the past or at the present. His father, the Commander of the Faithful (peace be upon him) has saved him to support his brother Imam Al-Hussayn (peace be upon him) with his own soul.
The blessings of his name:
According to the book "Muntakhab Attawarikh": "the name of Al-Abbas in terms of "ABC" calculations, the number of the letters of his name is 133 equalling the number of the letter of his title "Bab [Gate] Al-Hussayn (peace be upon him) that is also 133.
And among the supplications proven to facilitate the needs is repeating 133 times : "Ya Kashifa Al-Karbi 'an wajhi akhika Al-Hussayn ('alayhi assalam), Ikshif karbi bi haqqi akheeka Al-Hussayn ('alayhi assalam)." [O he who has removed the anguish of the face of your brother Al-Hussayn (peace be upon him), Remove my anguish in the name of your brother Al-Hussayn (peace be upon him).]