Nouns that are defective with respect to the number category (used only in singular (прах, “prah”, dust) or only in plural (анали, “anali”, annals), always have respectively only singular lemmas and only plural lemmas. The information about their usage is presented in a lemma marker.

• Professions, roles, titles and ranks for men and women are united in one synset, which has equivalent-to relation with the EWN synset for the noun for men and a near-equivalent-to relation to the EWN synset for women if such is present. Here is an example: сервитьор, “servitjor”, waiter and сервитьорка, “servitjorka”, waitress are in one synset that has equivalent-to relation with waiter and near-equivalent-to with waitress.
• Another approach is taken towards the nouns for male and female relatives and for male and female animals - they belong to different synsets. Here is an example: баща, “bašta”, father and майка “majka”, mother are in separate synsets and each has equivalent-to relation with respectively father and mother from EWN. Both баща and майка have the synset родител, “roditel”, parent as a hypernym.
• Nouns for young animals are presented as synset members of the general meaning of the given animal. Here is an example: овен, “oven”, ram, овца, “ovca”, sheep and агне, “agne”, lamb are in one synset with equivalent-to relation with sheep and near-equivalent-to relation with ram and lamb.
• Nouns for male and female title and rank holders are members of one synset. Here is an example: дон, “don”, Don and доня, “donja”, донa, “dona”, Dona are in one synset with equivalent-to relation with Don and near-equivalent-to relation with
• Forms of addressing men and women are in one synset. Here is an example: батко, “batko” (used for addressing older men) and кака, “kaka” (used for addressing older women) are in one synset which has обръщение, “obrǎštenie” (address) as a hypernym.
  Meanwhile an exception are господин, “gospodin”, Mister and госпожа, “gospoža”, Mrs. which are in separate synsets and each has equivalent-to relation respectively with and Mrs. Both господин and госпожа have обръщение “obrǎštenie” (address) as a hypernym.
• Diminutives are members in the synset of the general form of the given word. Here is an example: стол, “stol”, chair and столче, “stolče”, chair-diminutive are in one synset.

In this category are also included participles which function as adjectives under two conditions - a participle is either independently presented in the dictionaries or it is determined as a synonym of an adjective.

Here is an example: in the synset with дебел, “debel”, fat are added a few participles as synonyms: охранен, “ohranen”, угоен, “ugoen” respectively from the verbs охраня, “ohranya” and угоя, “ugoya” (make a person/animal to gain weight with a rich diet), and хранен, “hranen” from храня, “hranja”, feed.

Ordinal numerals (for example, трети, “treti”, third) are presented with the adjective category in BTB-WN as it is done in the OEW.

Both types of Bulgarian adjectives  - qualitative (which express intrinsic properties and qualities of an object, for example красив, “krasiv”, beautiful) and relative (which reflect qualities and properties of objects in relation to another object, for example правоъгълен, “pravoǎgǎlen”, rectangular) - are included in BTB-WN.

The two types of Bulgarian adverbs are presented in BTB-WN - regular (derived from nouns, adjectives, numerals, verbs, prepositions, for example бързо, bǎrzo, quickly) and pronominal adverbs (derived from pronouns, for example тук, tuk, here).

Adverbs from all semantic types are included in BTB-WN - qualitative, quantitative, purpose, locative, temporal, etc.

Impersonal verbs have lemmas in third person singular. Here is an example: оказва се, “okazva se”, окаже се, “okaže se”, turn out, prove, turn up are in third person singular.

Prefixed verbs with semantics for beginning, end, duration, etc. of the action are synset members to the general form of the given verb.

Here is an example: чета, “četa”, read is in one synset with зачета, “začeta”, зачитам, “začitam”, start to read, попрочета, “popročeta”, попрочитам, “popročitam”, read a little, partly, пречета, “prečeta”, пречитам, “prečitam”, read again and so on.