conforming with or constituting a norm or standard or level or type or social norm; not abnormal | established or well-known or widely recognized as a model of authority or excellence |
in accordance with scientific laws | conforming to or constituting a standard of measurement or value; or of the usual or regularized or accepted kind |
being approximately average or within certain limits in e.g. intelligence and development | conforming to the established language usage of educated native speakers |
forming a right angle | commonly used or supplied |
| regularly and widely used or sold |