the GNU version of the Collaborative International Dictionary of English
In the month immediately preceding the present; ; -- usually abbreviated to ult. Cf. proximo.
The Century Dictionary and Cyclopedia
In the month which preceded the present; in the last month, as distinguished from the current or present month and all others.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adj. in or of the month preceding the present one
Word Usage
"A pair of diverticula arise from the fifth branchial pouch and form what are termed the ultimo-branchial bodies (Fig. 1175): these fuse with the thyroid gland, but probably contribute no true thyroid tissue."