masculine, nominative plural (satthanti = satthaṃ + iti, 'weapons/caravans are')
Analysis. satthaṃ + iti: nominative plural sattha + the particle iti ('thus, so'), here used as a quotative or assertive marker turning the noun into a predicate phrase or utterance ('weapons/caravans being so', or 'they are weapons/caravans').
Etymology. From Proto-Indo-European *stegʰ- 'to cover, protect', whence Sanskrit śastram 'weapon' and Sanskrit śastṛ 'teacher' (one who instructs/protects through doctrine). The concrete image: a weapon as what shields or protects. The semantic shift from 'weapon' to 'science, art, lore' reflects the sense of an art or discipline as a tool or instrument of the mind. Related to Latin tegere 'to cover'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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