Indistinctness in a written instrument is ambiguity.

Explanation

(English-origin maxim.) Any indistinctness in a written instrument — whether from unclear phrasing, conflicting provisions, or uncertain reference — constitutes ambiguity and opens the door to construction; whether extrinsic evidence is admissible to resolve it depends upon whether the ambiguity is patent (apparent on the face — see 10.3.5) or latent (revealed only by application to the facts — see 10.3.4).

Where this applies

• A lease says the tenant may use the premises for "business purposes" without specifying what kind of business — the indistinctness of the phrase creates ambiguity about whether a restaurant qualifies.
• A contract requires delivery of goods in "good condition" — the phrase is indistinct enough that the parties genuinely disagree about what quality standard was intended.
• A will directs the executor to distribute assets "fairly" among the heirs without further instruction — the vagueness of "fairly" is itself an ambiguity that opens the door to construction.