The meaning of the word Arihant is Whose enemies are all finished or who does not have any enemy.You can also give it the meaning that desires are your enemies and Arihant is the one who has destroyed all the desires.
Arihanta is the name in Jainism, as arhat is in Buddhism, for one who has achieved the ultimate or god or moksha.
The Arihanta Mantra is:
Namo arihantanam Namo siddhanam Namo aayreeyaanam Namo uvajjhayanam Namo loye savva sahunam
"Namo Arihantanum ", means that I am bowing to the Arihant Bhagwan , the One who has destroyed the internal enemies in the form of anger, pride, passion and greed and yet walks about in human form.
"Namo Siddhanum " , means I am bowing and offering namaskaars...obeisance to the Siddha Bhagwan, the One who is Siddha..who has attained moksha and does not have a body.
"Namo Aayareeyaanum", we are bowing to the Acharya or the Principal Bhagwant who is fully Self Realised and imparts Gnandaan...The Knowledge of The Real to others.
"Namo Uvazzayanum" the Upadhyaya means the teacher who has received Atmagnan..the knowledge of the Self, but are in the process of progressing towards full Realisation, and are also teaching others the way and the method.
"Namo Loye savvasahunum " renders obeisances to all sadhus...saints of this world. But who can be called a saint ? This ascetic with the ochre robes ? No. Only the one who strives for establishment of the state of the Self, and no body else can be called a sadhu or a saint.
"Aiso panch namukkaro..." to these five I bow. " Savva paavvapanaashano.." means this destroys all sins. " Mangalanum cha savve sim, padhham havai mangalam " means of all that is auspicious this is the highest, the most.