Meaning of PLAIN in English
1.adj., adv., & n.
1. clear; evident (is plain to see).
2 readily understood; simple (in plain words).
3 a (of food, sewing, decoration, etc.) uncomplicated; not elaborate; unembellished; simple. b without a decorative pattern.
4 (esp. of a woman or girl) ugly.
5 outspoken; straightforward.
6 (of manners, dress, etc.) unsophisticated; homely (a plain man).
7 (of drawings etc.) not coloured (penny plain, twopence coloured).
8 not in code.
1. clearly; unequivocally (to speak plain, I don't approve).
2 simply (that is plain stupid).
1. a level tract of esp. treeless country.
2 a basic knitting stitch made by putting the needle through the back of the stitch and passing the wool round the front of the needle (opp. PURL(1)).
Phrases and idioms:
be plain with speak bluntly to. plain card neither a trump nor a court-card. plain chocolate dark chocolate without added milk. plain clothes ordinary clothes worn esp. as a disguise by policemen etc. plain-clothes (attrib.) wearing plain clothes. plain cook a person competent in plain English cooking. plain dealing candour; straightforwardness. plain sailing
1. sailing a straightforward course.
2 an uncomplicated situation or course of action. plain service Eccl. a church service without music. plain-spoken outspoken; blunt. plain suit a suit that is not trumps. plain text a text not in cipher or code. plain time time not paid for at overtime rates. plain weaving weaving with the weft alternately over and under the warp.
plainly adv. plainness n.
Etymology: ME f. OF plain (adj. & n.) f. L planus (adj.), planum (n.) 2. v.intr. archaic or poet.
3 make a plaintive sound.
Etymology: ME f. OF plaindre (stem plaign-) f. L plangere planct- lament
Oxford English vocab. Оксфордский английский словарь. 2012