participial

1. not comparablegrammarOf, relating to, or being a participle.

plural participials

1. datedgrammarA non-finite verb.

   […] the verb has two forms, which […] are called Participials, namely, (a) The Infinitv […] (b) The Participle […] .

   1870, Raphael Kühner (original author), Samuel H. Taylor (English translator), An Elementary Grammar of the Greek Language, 20th ed., p. 75

   2 more examples

   § 280. A Participial is a derived form of the verb used not for asserting but for expressing either, — 1. An object of thought; or, 2. A modification of such an object. Participials, accordingly, are either, — 1. Noun-participials; as, "To think is to act;" "Their sending the messacre was the cause of the trouble;" or, 2. Adjective-participials, more commonly called Participles; as, "The advancing army;" "The expected messenger."

   1867, Henry Noble Day, The art of English composition, page 151

   To have a short appellation, let us call participles and infinitives participials. Among all the myriads of words, a more skillful, many-sided and hard-working class than this could hardly be found, and still—such is the world's reward—they are strangers in a strange land forced to live with their aristocratic cousins, the "finite" verbs. For participials are not verbs in reality.

   1889 March, P. Magnie Magnusson, “Participles and infinitives”, in School Education, volume 8, page 56

2. A participial word.

   Synonyms: participle