From Middle English explanen, from Old French explaner, from Latin explanō, from ex- ("out") + planō ("I flatten, make level"), from planus ("level, plain"); see plain and plane.

• IPA: /ɪkˈspleɪn/, /ɛkˈspleɪn/

explain (explains, present participle explaining; simple past and past participle explained)

1. (ambitransitive) To make plain, manifest, or intelligible; to clear of obscurity; to illustrate the meaning of.

   She is about to explain a chapter of the Bible to the Sunday School students.

   She tried to explain but he wouldn’t listen.

   • 1909, Archibald Marshall [pseudonym; Arthur Hammond Marshall], “A Court Ball”, in The Squire’s Daughter, New York, N.Y.: Dodd, Mead and Company, published 1919, →OCLC ↗, page 9 ↗:

     The boy became volubly friendly and bubbling over with unexpected humour and high spirits. He tried to persuade Cicely to stay away from the ball-room for a fourth dance. Nobody would miss them, he explained.

2. (transitive) To give a valid excuse for past behavior.
3. (obsolete) To make flat, smooth out.
4. (obsolete) To unfold or make visible.
   • April 14, 1684, John Evelyn, a letter sent to the Royal Society concerning the damage done to his gardens by the preceding winter

     The horse-chestnut is […] ready to explain its leaf.

5. (intransitive) To make something plain or intelligible.

• (give a sufficiently detailed report) expound, elaborate, recce

• explanation
• explanatory
• explanatorily

• French: expliquer
• German: erklären, erläutern
• Italian: spiegare, chiosare, illustrare
• Portuguese: explicar, explanar
• Russian: объясня́ть
• Spanish: explicar

• French: justifier
• German: erklären
• Italian: giustificare, motivare, scusarsi
• Portuguese: explicar
• Russian: опра́вдывать
• Spanish: explicar