extra: [18] In its modern English use, ‘beyond what is normal’ or ‘additional’, extra is probably an abbreviation of extraordinary [15], in which the prefix represents Latin extrā ‘outside, beyond’. This in turn was short for exterā, the ablative feminine case of the adjective exterus ‘outer’ (from which English gets exterior [16]). And exterus itself began life as a compound form based on Latin ex ‘out’. => exterior, extreme
extra
1650s as a stand-alone adjective; also used as an adverb and noun in 17c. (see extra-); modern usages -- including sense of "minor performer in a play" (1777) and "special edition of a newspaper" (1793) -- probably all are from shortenings of extraordinary, which in 18c. was used extensively as noun and adverb in places extra would serve today.
例文
1. She gave him an extra scoop of clotted cream.
彼女は彼に濃縮クリームを1杯追加した。
2.The President is determined "to go the extra mile for peace ".
大統領は「平和を実現するために努力を倍加する」と決意した。
3.There 's an extra blanket in the bottom drawer of the cupboard.
クローゼットの一番下の引き出しには、余分な毛布があります。
4.Police warned motorrists to allow extra time to get to work.
警察は運転者に出勤するために余裕を持つよう警告した。
5.Stay in bed extra late or get up specially early.