-al; -ial, -eal

(Latin: suffix; pertaining to, like, of the kind of, relating to, characterized by, belonging to; action of, process of)

asocial (adjective), more asocial, most asocial
1. Unable or unwilling to conform to normal standards of behavior with other people: Helena was a very asocial individual who always did what she wanted despite what was typically acceptable by others.
2. Inconsiderate of others and more interested in oneself than in other people: Hector’s mother was always cautioning him not to be such an asocial person when he was playing with other children on the playground.
asterial
Starlike, a fossil starfish.
atlantoaxial
Referring to the atlas and the axis; denoting the joint between the first two cervical vertebrae.
atonal
Music that is played without harmony; lacking harmony; unharmonious.
atrial (adjective)
1. Relating to or belonging to the central area in a building that is open to the sky.
2. The chamber that is connected to other chambers or passageways; especially, one of the two upper chambers of the heart.
aural (air)
Characterized by or relating to an aura.
auspicial (adjective), more auspicial, most auspicial
Of or pertaining to a favorable sign or indicating that a future success is probable for an activity: "James found that it was an auspicial decision to apply for a new job after his previous employment was terminated because the company he worked for was decreasing the number of workers they had for economic reasons."
axial
Relating to, or operating, along an axis.
axial flow
Any flow parallel to an axis; especially, a flow in turbomachinery in which the flowing fluid always moves parallel to the length of the rotating shaft; as in an axial-flow turbine.
bacterial
balneal
Of or pertaining to baths or to bathing.
beneficial (adjective), more beneficial, most beneficial
Descriptive of that which brings about a positive result, is favorable, and good: Drinking lots of fresh water is a beneficial action which supports good health.
biaxial
biennial
1. Happening every two years.
2. Used to describe a plant that lives for two years and produces flowers and fruit in the second year.

Note: biannual means "twice a year"; which is, within the same year.

bilabial