Acceptable

adj. satisfactory, worthy of acceptance; admissible, suitable; bearable, tolerable

Proper may refer to:Proper (liturgy), the part of a Christian liturgy that is specific to the date within the Liturgical Year.Proper frame, such system of reference in which object is stationary (non moving), sometimes also called a co-moving frame.Proper, in heraldry, means depicted in natural colors.Proper or appropriate conduct.
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Adjective
1. worthy of acceptance or satisfactory; "acceptable levels of radiation"; "performances varied from acceptable to excellent"
(antonym) unacceptable
(similar) bankable
(see-also) satisfactory
2. judged to be in conformity with approved usage; "acceptable English usage"
(synonym) accepted
(similar) standard, received
(classification) linguistics
3. meeting requirements; "the step makes a satisfactory seat"
(synonym) satisfactory
(similar) good
4. adequate for the purpose; "the water was acceptable for drinking"
(similar) fit, fit to(a), fit for(a)

adj. adequate, acceptable, admissible; agreeable, fair, palatable; passable, possible

(a.)
Capable, worthy, or sure of being accepted or received with pleasure; pleasing to a receiver; gratifying; agreeable; welcome; as, an acceptable present, one acceptable to us.