What does 約 mean?
約 is a Japanese adverb meaning “approximately, about, some” in English. It can also be translated as “promise, shortening, contraction (in phonetics)” depending on context. It is written as 約 in kanji, やく in hiragana, and yaku in romaji. This word is part of JLPT N3 vocabulary.
Example sentence
その値段は約５０ドルだった。
The price was in the neighbourhood of 50 dollars.