havaitessaan

Havaitessaan is a participial form of the Finnish verb havaita, meaning to perceive or notice. It is a present active participle used to introduce an adverbial clause that states the circumstance under which the main clause occurs. The subject of the participle clause is normally the same as the subject of the main clause. The sense conveyed is approximately “when noticing,” “upon noticing,” or “having noticed,” depending on context and punctuation.

Usage of havaitessaan is common in written Finnish, especially in narratives and formal prose, where it helps to compress information that would otherwise require a finite subordinate clause. In everyday speech, speakers more often use conjunctions such as kun or kun hän huomasi to express similar meanings, or they rephrase the sentence to avoid the participial form.

Example:

Havaitessaan virheen ohjelma pysähtyi.

Translation: Having noticed the error, the program stopped.

Related forms include the past participle havaittu (noticed, perceived) and the present active participle havaitseva (noticing, perceiving). The verb itself is havaita, and havaitessaan represents one of several non-finite constructions available for linking clauses with a common subject in Finnish grammar.