Paul Leslie Gardner pioneered the study of student difficulties with everyday words presented in the science context (Gardner 1971); several similarly designed studies (e.g. Cassels and Johnstone 1985; Tao in "Research in Science Education," 24, 322-330, 1994; Farell and Ventura in "Language and Education," 12(4), 243-254, 1998; Childs and O'Farell in "Chemistry Education: Research and Practice," 4(3), 233-247, 2003) have since been reported in literature. This article 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. The participants (1107 learners and 35 respective physical science teachers) were drawn from 35 public secondary schools in Johannesburg area of South Africa. Data were obtained through a word test to participant learners followed by group interviews but face-to-face interviews with each physical science teacher. This study has revealed that in similar ways as have been reported in each of the studies so far, South African learners also face difficulties with meanings of everyday words presented in a science context. 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. Interpretations of learner interview responses revealed that fewer difficulties would have been experienced by learners if science teachers generally explained the context meanings of the words as used during science teaching. The findings suggest that focusing on 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 context on meanings of everyday words of the LOLT are discussed. This article stands as an evidence-led discussion of the issues around the language-related difficulties that learners in South Africa may encounter as they learn school science.