The module properties would have given you the answer. (Select the module, then, go to the main menu -> Dictionary -> Information. The popup window give this information.
Strong's Hebrew and Greek Dictionaries
Dictionaries of Hebrew and Greek Words taken from Strong's Exhaustive Concordance by James Strong, S.T.D., LL.D.
Published in 1890; public domain.
+ (addition) denotes a rendering in the Authorized Version of one or more Hebrew/Greek words in connection with the one under consideration.
X (multiplication) denotes a rendering in the Authorized Version that results from an idiom peculiar to the Hebrew/Greek.
° (degree), appended to a Hebrew word, denotes a vowel-pointing corrected from that of the text. (This mark is set in Hebrew Bibles over syllables in which the vowels of the margin have been inserted instead of those properly belonging to the text.)
( ) (parenthesis), in the renderings from the Authorized Version, denotes a word or syllable sometimes given in connection with the principal word to which it is annexed.
[ ] (bracket), in the rendering from the Authorized Version, denotes the inclusion of an additional word in the Hebrew/Greek.
Italics, at the end of a rendering from the Authorized Version, denote an explanation of the variations from the usual form.
Derivative Work, Copyright © 2002-2019 by Rick Meyers. All rights reserved.