Rhythmic \Rhyth"mic\ (-m[i^]k), Rhythmical \Rhyth"mic*al\ (-m[i^]*kal), a. [Gr. ????: cf. L. rhythmicus, F. rhythmique.]

Pertaining to, or of the nature of, rhythm [1913 Webster]

Day and night I worked my rhythmic thought. --Mrs. Browning. [1913 Webster]

Rhythmical accent. (Mus.) See Accent, n., 6
   (c) . [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

47 Moby Thesaurus words for "rhythmical": alternate, antispastic, beating, cadenced, cadent, circling, cyclic, dactylic, epochal, even, every other, iambic, in numbers, in rhythm, intermittent, isochronal, measured, metric, metronomic, oscillatory, palpitant, periodical, pitapat, prosodic, pulsatile, pulsating, pulsative, pulsatory, pulsing, pyrrhic, reciprocal, recurrent, recurring, rhythmic, rotary, scanning, seasonal, serial, spondaic, staccato, steady, throbbing, trochaic, undulant, undulatory, wavelike, wheeling

Source: Moby Thesaurus II by Grady Ward, 1.0
 

rhythmical adj : recurring with measured regularity; "the rhythmic chiming of church bells"- John Galsworthy; "rhythmical prose" [syn: rhythmic] [ant: unrhythmical]

Source: WordNet (r) 2.0
 

Rhythmic \Rhyth"mic\ (-m[i^]k), Rhythmical \Rhyth"mic*al\ (-m[i^]*kal), a. [Gr. ????: cf. L. rhythmicus, F. rhythmique.]

Pertaining to, or of the nature of, rhythm

Day and night I worked my rhythmic thought. --Mrs. Browning.

Rhythmical accent. (Mus.) See Accent, n., 6
   (c) .

Source: Webster's Revised Unabridged Dictionary (1913)