1. To bring to a likeness or to conformity; to cause a resemblance between. Sir M. Hale. To assimilate our law to the law of Scotland. John Bright. Fast falls a fleecy; the downy flakes Assimilate all objects. Cowper. 2. To liken; to compa [R.] 3. To appropriate and transform or incorporate into the substance of the assimilating body; to absorb or appropriate, as nourishm...