ラテン語のponere, to place, -st, 過去分詞格から、語源的にはposition, composite.と同じで、次の意味を持つ:1. post, stake, posting, posting; 2. military post, post, stationing; 3. old stagecoach, post horse, postman, post, mail; 4. immediately, right away, from the phrase to ride post, to ride a post.馬を乗り換える、急ぐ。