astra

In a sentence

• अपनी बुद्धि को ही अपनी शक्ति और अस्त्र बनाओ।

  Make your intellect your strength and weapon.

  Here 'astra' is used metaphorically to mean a tool or weapon, symbolizing something that aids in achievement.

• महाभारत में अर्जुन को अनेक अस्त्रों का ज्ञान था।

  Arjuna in the Mahabharata had knowledge of many weapons.

  In this context, 'astra' refers to actual weapons, especially those of divine or magical nature.

• संवाद में शब्द ही अस्त्र हैं।

  In communication, words themselves are weapons.

  Again, 'astra' is metaphorically indicating tools or methods used to achieve a goal, specifically in the context of communication.