Entry 1 sense Webster, 1913 Abietic · Ab·i·et·ic · IPA /ˌæb.iˈɛt.ɪk/ 01 a. Of or pertaining to the fir tree or its products; as, abietic acid, called also sylvic acid. 1. Of or pertaining to the fir tree or its products; as, abietic acid, called also sylvic acid.