The literal meaning of the Arabic term %u2018Jihaad%u2019 means to strive, or exert one%u2019s efforts, or earnestly work towards a desired goal.
Allah Says in the Holy Quran Chapter 61 Surah Saff verses 10-12:
10 O ye who believe! Shall I lead you to a bargain that will save you from a Grievous Penalty?
11 That ye believe in Allah and His Messenger and that ye do %u2018jihaad%u2019 (strive your utmost) in the Cause of Allah with your property and your persons: that will be best for you if ye but knew!
12 He will forgive you your sins and admit you to Gardens beneath which rivers flow, and to beautiful mansions in Gardens of Eternity: that is indeed the Supreme Achievement.
Any striving, any effort, or any work or thing one does in the Cause of Allah or to further the Cause of Islam, seeking nothing but the Pleasure and Good Will of their Lord Most High would be considered %u2018jihaad-fi-Sabeelillah%u2019 (Jihaad in the Cause of Allah) in the Sight of Allah Subhanah.
In light of the guidance of the Glorious Quran and the authentic and established Sunnah of the Messenger of Allah (saws), the absolute minimum level of %u2018jihaad%u2019 is to strive against one%u2019s own soul and temptations and control one%u2019s unlawful desires%u2026.and the highest level or epitome of %u2018jihaad%u2019 in Islam is to be ever ready to willingly lay down (if need be) one%u2019s life and one%u2019s property to further the Cause of Allah Subhanah.