become hooked on

２２日に配信が始まったスマートフォン用ゲームPokemon GOで遊びながらバイクを運転する若者が京都で相次いで逮捕されました。

Police ‘catch’ 2 motorcyclists illegally playing ‘Pokemon Go’

KAMEOKA, Kyoto Prefecture--Instead of searching for Pokemon (pocket monsters) on their smartphones, police officers in Japan are on the lookout for drivers who are dangerously playing "Pokemon Go" on the roadways.

On July 22, the day the popular app was released in Japan, a police officer in Kameoka ticketed a 22-year-old man on suspicion of violating the Road Traffic Law by using a smartphone while driving.

The man was ticketed after the officer noticed him snaking his way along National Route 423 on his scooter around 11:55 p.m. He was found to be playing "Pokemon Go" on his smartphone when he was stopped by police.

The next day, a police officer in Kyoto spotted a youngster looking at his smartphone while riding a motorcycle about 4 p.m. in the city’s Kita Ward. The 19-year-old was ticketed on suspicion of violating the law. His smartphone’s display also showed “Pokemon Go” in use.

According to the officers, both men said they became hooked on the game and continued to play even while driving.

http://www.asahi.com/ajw/articles/AJ201607240022.html

今回取り上げる表現は、“become hooked on”です。『ウィズダム英和辞典』(第３版、三省堂)を引いたところ、“get [be] hooked on A”で「A〈麻薬など〉の中毒になる[なっている]；A〈音楽・インターネットなど〉に夢中になる[なっている]」とありました。今回は、“become hooked on”という形ですが、意味は同じだと思われます。

Macmillan Dictionary.comでは、“if you are hooked on something, you find it so attractive or interesting that you want to do it as much as possible”と定義されていました。

“hook”には「(物をひっかける)かぎ、フック」という意味があります(『ウィズダム英和辞典』)。そこから、「(人が)〜に夢中になる」という表現を、「(人が)何かに引っかかる」というように例えているのだと思います。(Blue Sky)