troscadh, m. (gs. -aidh, pl. -aí).1. vn. of troisc1. 2. Fast. Bheith i do throscadh, to be fasting. Chuaigh mé ann i mo throscadh, I went there fasting, without having breakfasted. ~ a dhéanamh, to fast, to observe an ecclesiastical fast. An té a bhfuil ~ air, he who is bound to fast. Má tá ~ ar fheoil, if flesh-meat is forbidden. Lá troscaidh, fast-day. ~ an anama, Ember-days. S.a. tréanach1.