Standard, boring

adjective

1. Lacking ornament undecorated
2. Free of extraneous matter pure
3. Free of impediments to view unobstructed
4. Marked by outspoken candor free from duplicity or subtlety blunt

   "plain talk"

5. Belonging to the masses common
6. Lacking special distinction or affectation ordinary
7. Characterized by simplicity not complicated

   "plain home-cooked meals"

8. Lacking beauty or ugliness
9. Even, level

noun

1. An extensive area of level or rolling treeless country
2. A broad unbroken expanse
3. Something free from artifice, ornament, or extraneous matter

adverb

1. In a plain manner without obscurity or ambiguity

   "saw them clearly and told you plain"

adverb

1. Absolutely

   "plain wrong"

verb

1. Complain

noun

1. Civilian clothes the dress of an ordinary citizen

   "… he had brought in a stenographer, more cops, and an older man in plain clothes."

adjective

1. Not fancy or glamorous ordinary

noun

1. One that is plain

adjective

1. Consisting of three strands laid right-handed compare cable-laid

noun

1. Members of any of various Protestant groups (such as Mennonites) especially in the U.S. who wear distinctively plain clothes and adhere to a simple and traditional style of life excluding many conveniences of modern technology