  Learning vocabulary in a primary or secondary language is enhanced when we
encounter words in context. This context can be afforded by the place or
activity we are engaged with. Existing learning environments include formal
learning, mnemonics, flashcards, use of a dictionary or thesaurus, all leading
to practice with new words in context. In this work, we propose an enhancement
to the language learning process by providing the user with words and learning
tools in context, with VocabulARy. VocabulARy visually annotates objects in AR,
in the user's surroundings, with the corresponding English (first language) and
Japanese (second language) words to enhance the language learning process. In
addition to the written and audio description of each word, we also present the
user with a keyword and its visualisation to enhance memory retention. We
evaluate our prototype by comparing it to an alternate AR system that does not
show an additional visualisation of the keyword, and, also, we compare it to
two non-AR systems on a tablet, one with and one without visualising the
keyword. Our results indicate that AR outperforms the tablet system regarding
immediate recall, mental effort and task completion time. Additionally, the
visualisation approach scored significantly higher than showing only the
written keyword with respect to immediate and delayed recall and learning
efficiency, mental effort and task-completion time.
