This chapter draws from an exploratory study of the difficulties South African High School physical science learners encounter with everyday English words when presented in the science context. Data were obtained from participants (1107 learners and 35 respective physical science teachers/educators from 35 public secondary schools in Johannesburg area of South Africa) through a word test to participant learners followed by group interviews but one-on-one interviews with respective physical science educators. Findings have revealed that South African learners also face difficulties with meanings of everyday words presented in the science context. While the main source of difficulties encountered was learner inability to distinguish between the meanings of familiar everyday words as used in everyday parlance from the ‘new’ meanings of the same everyday words when used in the science context, fewer difficulties will be experienced by learners if science educators (1) take to being more precise in their talk and use of language, and/or (2) generally explain the nature and context meanings of all the words used during teaching. The findings thus suggest that focusing on precise use of language as well as contextual proficiency more than on general proficiency in the language of learning and teaching (LOLT) during teaching perhaps holds more promise for enhanced learning and achievement in science. Steps necessary to raise teacher awareness of the potential impact of attention to precise use of language, nature and context meanings of everyday words of the LOLT science are discussed.