Interpretation of genetic results
You are right about the cDNA 341 nucleotide deletion.
It is an exon deletion, meaning that the deletion is part of a gene that encodes to a protein.
This corresponds to the second part - the protein level (annotated with p.).
The mutation that is caused on the protein level is a frameshift mutation (corresponds to the fs).
A frameshift mutation changes the reading frame of the protein.
You can find more information on frameshift mutations annotations on the HGVS nomenclature website.

In your case (p.Thr114Lysfs*37) the annotation indicates that the cDNA 341 nucleotide deletion led to a frameshift mutation of the protein with a Thr amino acid residue being replaced by a Lys amino acid residue. Furthermore, this also altered when the protein terminates: there is a new translation termination (stop) codon after 37 amino acid residues instead of terminating at the end of the protein where it normally does.