Abac definitions

Abac

1) Certain quatrain pattern 2) Common rhyme scheme 3) Rhyme scheme 4) Scheme for a quatrain
Found on https://www.crosswordclues.com/clue/abac

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Abac

An abac is a two dimensional matrix or table that shows the distances between major towns etc. Abacs are often found at the back of a road atlas.
Found on http://www.probertencyclopaedia.com/browse/AA.HTM

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