  Purpose: Terminology is the set of technical words or expressions used in
specific contexts, which denotes the core concept in a formal discipline and is
usually applied in the fields of machine translation, information retrieval,
information extraction and text categorization, etc. Bilingual terminology
extraction plays an important role in the application of bilingual dictionary
compilation, bilingual Ontology construction, machine translation and
cross-language information retrieval etc. This paper addresses the issues of
monolingual terminology extraction and bilingual term alignment based on
multi-level termhood.
  Design/methodology/approach: A method based on multi-level termhood is
proposed. The new method computes the termhood of the terminology candidate as
well as the sentence that includes the terminology by the comparison of the
corpus. Since terminologies and general words usually have differently
distribution in the corpus, termhood can also be used to constrain and enhance
the performance of term alignment when aligning bilingual terms on the parallel
corpus. In this paper, bilingual term alignment based on termhood constraints
is presented.
  Findings: Experiment results show multi-level termhood can get better
performance than existing method for terminology extraction. If termhood is
used as constrain factor, the performance of bilingual term alignment can be
improved.
