The Japanese verb '咲く (さく)' means 'to bloom' or 'to flower'. It is specifically used to describe the blooming of flowers, such as cherry blossoms, roses, or other plants. This verb is often used in contexts related to nature, seasons, and beauty. For example: The cherry blossoms are blooming「桜が咲いている」(さくらがさいている). The flowers in the garden bloomed beautifully「庭の花がきれいに咲いた」(にわのはながきれいにさいた). Note that this verb is intransitive, meaning it does not take a direct object.