Sensu is a Latin term meaning "in the sense of". It is used in taxonomy to specify which circumscription of a given taxon is meant, where more than one circumscription has been defined.

It is commonly used in the phrase sensu stricto ("in the stricter sense") (abbr.: s.s.), to specify that the circumscription with the smaller number of members is intended.^[1]

The opposite of sensu stricto is sensu lato ("in the wider sense") (abbr.: s.l.).^[2]

In rare cases in which several different circumscriptions have been used, the superlatives sensu strictissimo ("in the strictest sense") and sensu latissimo ("in the widest sense") may be used.

Another common usage is in conjunction with an author citation, indicating that the intended circumscription is the one defined by that author. For example, the phrase specifies Alex George's circumscription of B. subg. Banksia.

References

1. ↑
2. ↑