Incertum

• (a.) Doubtful; not of definite form.
Found on http://thinkexist.com/dictionary/meaning/incertum/

Incertum

In┬Ěcer'tum adjective Doubtful; not of definite form. Opus incertum (Anc. Arch.) , a kind of masonry employed in building walls, in which the stones were not squared nor laid in courses; rubblework.
Found on http://www.encyclo.co.uk/webster/I/31
No exact match found