IMac6:51 :ܠܡܫܕܐ ܒܒܠܣܛܘܣ ܓܐܪ̈ܐ ܘܟܐ̈ܦܐ ܘܢܘܪܐ‏ : to hurl arrows, stones, and fire with the ballista
See the entire entry for blsṭs n.m. ballista