In a somewhat cheap or inexpensive manner; rather poorly or stingily.
Cheapish plus -ly, an adverb-forming suffix. This creates an adverb from an adjective (cheapish) that itself was derived from an adjective (cheap) with -ish, showing how English stacks suffixes.
Words like 'cheapishly' showcase English's amazing flexibility—you can technically stack multiple derivational suffixes, but the result often sounds awkward, which is why many potential words never catch on in actual speech.
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