Not easy to tell, it seems. This may be a word, but it is uncertain. Though the inclination of the OED is against it, they still do not list it as a spurious word, though I will tag it thus because of the possibility.
[An entry copied from Dict. to Dict. since 17th c.; its source has not been ascertained; and as the form of the word does not admit of explanation, there is ground to suspect its origination in some error in the transcription of a L. or OFr. document. If the word existed, and is correctly explained, it would be a square acre, i.e. a piece of land a furlong square = 48,400 sq. yds.]