Principal English Translation: 
sometime, on some occasion (see Karttunen)
Alonso de Molina: 
ica.  en algun tiempo, o alguna vez.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 31v. col. 2.  Thanks to Joe Campbell for providing the transcription.
Frances Karttunen: 
ICAH sometime, on some occasion / en algún tiempo o alguna vez (M).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 92.
Horacio Carochi / English: 
Attestations from sources in English: 
ica (adverb) = sometimes occasionally
Daniel Garrison Brinton, Ancient Nahuatl Poetry: Containing the Nahuatl Text of XXVII Ancient Mexican Poems (1887), 154.