In American English, you say 'soccer player'.
However, soccer is only said in North America (the United States, Canada), Australia, and South Africa. Almost everywhere else in the world, the sport is called 'football.'
In America/Australia, football refers to the sport with the pointed ball, where you carry the ball in your hands. In countries where 'football' means the sport you play with your feet, they call it 'American football'.
Each player has a part on the team; a professional soccer player can also be called a defender, goalie, fullback, etc.
itoさん、こんばんは。
サッカーはアメリカで "soccer" が多く使われていますが、殆どの国では "football" の方が普通に使われている言葉です。
player だけでも、普通に文脈で「プロ」という意味合いがもう予め入っていますが、敢えてそれを強調したいなら pro footballer 又は professional footballer 又は professional football player を使えます （soccer player でも大丈夫ですが soccerballer という言い方はないですーご注意下さい！）
ご参考になれば幸いです。
Someone whose job it is to play soccer is called a "professional soccer player."
In some countries such as the UK, soccer is called "Football" so they are called professional football players.
EG:
Frank Lampard is a professional football player.
I want to be a professional soccer player when I grow up.
サッカーをプレイする人の仕事は、professional soccer playerと呼びます。
UKのような一部の国々では、サッカーはFootballと呼び、professional football playersと呼びます。
例：
Frank Lampard is a professional football player.
フランク・ランパードは、プロのサッカー選手です。
I want to be a professional soccer player when I grow up.
大きくなったら、私はプロのサッカー選手になりたいです。
In the UK, we call it 'football' and in the US, they call it 'soccer'. So a professional player is called 'a professional football player.'
""John's a professional football player."
イギリスでは「football」、アメリカでは「soccer」と言います。プロの選手は「a professional football player」と呼ばれます。
John's a professional football player.
（ジョンはプロのサッカー選手です。）
こんにちは。
「サッカー選手」は soccer player と言えます。
「プロの」を強調したい場合は professional を付け加えることも可能です。
なお、「サッカー」の呼び方は国によって異なります。
アメリカでは soccer ですが、イギリス等では football になります。
【例】
I want to be a soccer player when I grow up.
「将来はサッカー選手になりたい」
ぜひ参考にしてください。
In England, we use the word "football" instead of "soccer". If you are talking about a player, then they are usually called a "footballer". In most cases, just saying the word "footballer" would mean a professional, but you could add the word "professional" to the front if you wanted to emphasise this point.
A person who plays soccer as a profession (i.e for a living) is most commonly called a "Professional soccer player" or a "Football player". In England, we call soccer 'football'. However, America also refers to football as 'soccer'. Soccer or Football is the game of usually 11 people kicking a round a pitch with the aim of kicking that ball into the rival teams goal.
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