undulating

undulating (comparative more undulating, superlative most undulating)

1. Moving up and down like waves; wavy.
   • 1960 February, J. N. Faulkner, “The Belgian Railways today”, in Trains Illustrated, page 86:

     The Borinage coalfield around Mons is another attractive area for the railway enthusiast; it is rather like South Lancashire, with its gently undulating landscape studded with slag heaps and pithead gear and criss-crossed by railway lines and tramways.

2. Forming a series of regular curves.

undulating

1. present participle and gerund of undulate

undulating (plural undulatings)

1. undulation
   • 1930, John Thomas Ingram Bryan, The Philosophy of English Literature, page 27:

     In good poetry every word and phrase, as Professor McKail says, reverberates like the sound of a lyre, and leaves after it numberless undulatings. The verse exhales sweet sound, and light-like thought, as perfumes do; but we cannot explain just why.