adj., adv., & n.
—adj.
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.
—adv.
1 clearly; unequivocally (to speak plain, I don't approve).
2 simply (that is plain stupid).
—n.
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.
Derivatives:
plainly adv. plainness n.
Etymology: ME f. OF plain (adj. & n.) f. L planus (adj.), planum (n.)
2.
v.intr. archaic or poet.
1 mourn.
2 complain.
3 make a plaintive sound.
Etymology: ME f. OF plaindre (stem plaign-) f. L plangere planct- lament
Useful english dictionary. 2012.