Bekhorot 24: words to know

אִיבַּעְיָא לְהוּ (iba'ya lehu): a dilemma was raised by them. Introduces the inquiry analyzing Rabban Shimon ben Gamliel's reasoning.
לְמַאי נָפְקָא מִינַּהּ (lema'i nafka minah): what practical difference arises from it?. Asks what practical halakhic difference the two interpretations produce.
אוֹתוֹ וְאֶת בְּנוֹ (oto ve'et beno): slaughtering a parent animal and its offspring together. Mentioned as the practical case where maternal identity determines liability.
תֵּיקוּ (teiku): let it stand unresolved. Concludes the Gemara's unanswered dilemma regarding the nursing pig.
דָּבָר שֶׁאֵין מִתְכַּוֵּין (davar she'ein mitkaven): an unintentional act. Suggested as a reason why inadvertently plucking hair is permitted.