Of, relating to, or being an estimate or approximation.(adjective)
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Use "approximative" in a sentence
"(The amounts are approximative and come from public figures.)"
"Moral or extrapatrimonial damage is often difficult to put a figure on in an exact or even approximative manner."
"The tune sounded consistent, but the lyrics a little approximative in places (including a reference to ketchup which I strongly suspected had no business being there whatsoever)."