-al

{-al} is a suffix that occurs in English, which can either be a adjective suffix or a noun suffix.

As an adjective suffix, it is used to form adjectives meaning “of or pertaining to” from nouns, such as base → basal, cranium → cranial. etc.

As a noun suffix, it is used to form nouns “especially of verbal action” from verbs. Examples include bestowal, denial, proposal, etc.

If the root word contains l, the variant -ar is often used instead (e.g. solar, lunar, columnar, lumbar), unless the root contains r after the l (lateral, plural). Sometimes both forms are found: linear, lineal. ⟨-ial⟩, as in manorial is also possible.

This suffix is sometimes spelt ⟨ual⟩, e.g. sex → sexual. And it also sometimes occurs as {-el} in French-to-English loans, such as matériel, novel and personnel.

As a nominaliser, some verbs have two corresponding nouns, one ending in {-al} and the other in {-ion} (more common suffix), with one or the other being more common, sometimes with different nuances. Common examples: disposition/disposal (from dispose), proposition/proposal (propose), submission/submittal (submit), transmission/transmittal (transmit). Some superficial pairs are actually of different origin, notably reversion/reversal (revert/reverse, not both from reverse).